The width of a rectangular room is 40% of its length. If the length is 20 feet, what is the area of the room?

Answers

Answer 1

Answer:

160 ft^2

Step-by-step explanation:

First you have to find the width, then you find the area. To find the width with a percentage we do Part/ Total = %/100  and we cross multiply. We need to find the part so that is the unknown, we will call it 'w' for width

w/20 = 40/100       Now we cross multiply, the x and the 100 and the 20 and 40

w * 100 = 100w

20 * 40 = 800

Now we have 100w = 800      The next step is to divide both sides by 100 so we just have w

100x/100= w

800/100 = 8

w = 8

The width is 8

Now we find the area which is length x width

20 x 8 = 160

So the area is 160 ft^2


Related Questions

3) Paul bought 2 muffins, 2 brownies and I cookie at a bake sale. The muffins cost $1.30
each, the brownies cost $0.75 a piece and the cookie was $0.50. If he paid with a twenty
dollar bill, how much change should he get back?

Answers

Answer:

$15.40

Step-by-step explanation:

1.30 × 2 = 2.60

0.75 × 2 = 1.50

2.60 + 1.50 + 0.50 = 4.60

20 - 4.60 = 15.40

-6h+7=-17 what would h equal.

Answers

Answer:

4

Step-by-step explanation:

Answer:

4

Step-by-step explanation:

-6x__ should equal -17 so my best choice would to guess and check

if we do 5 that will give us -23 i believe

if we do 4 it gives us -17 so this would be our answer 4

First, we need to figure out how much you want to borrow. You said you wanted to spend $5,000, and you will put $500 down. Based on that, we can estimate your taxes to be $340. Put those numbers to see how much money you will need for your loan.​

Answers

Answer: You will need $4,160 for the loan.

The money that will need for the loan is $4160.

What is down payment?

A down payment is a sum of money the buyer pays at the outset of a large transactions. The down payment represents a portion of the total purchase price, and the buyer will often take out a loan to finance the remainder.

For the given situation,

The total amount wanted to spend = $5000

Down payment = $500

Tax amount = $340

Money that will need for the loan can be calculated as

⇒ [tex]5000-(500+340)[/tex]

⇒ [tex]5000-840[/tex]

⇒ [tex]4160[/tex]

Hence we can conclude that the money that will need for the loan is $4160.

Learn more about down payments here

https://brainly.com/question/16330592

#SPJ2

Ava washes 12 % windows in /hour. At this rate, how many windows can
she wash in one hour? ​

Answers

Answer:

She will wash 24% windows in one hour

Step-by-step explanation:

If Ava washes 12% windows in half hour

Since 2 half hours makes one hour

Therefore, 2 × 12% will be washed in one hour

That is, Ava will wash 24% windows in one hour

A chemist needs 500mL of 20% acid and 80% water mix for an experiment. He adds x mL of a 10% acid and 90% water and y mal of a 30% acid and 70% water mix to the 20% acid and 80% water mix. Find the amounts x and y

Answers

Answer:

  x = y = 250 mL

Step-by-step explanation:

The desired concentration of acid (20%) is exactly halfway between the concentrations of the available supplies (10%, 30%). So, the mix will be equal parts of each of those. x and y are both half the total quantity required:

  x = y = (500 mL)/2 = 250 mL

_____

If you need an equation to solve this, you can let x = 500 -y and write the equation for the acid volume in the final mix:

  10%(500 -y) +30%(y) = 20%(500)

  50 -0.1y +0.3y = 100 . . . . . eliminate parentheses

  0.2y = 50 . . . . . . . . . . . . . . subtract 50, collect terms

  y = 250 . . . . . . . . . . . . . . . multiply by 5 (equivalently, divide by 0.2)

  x = 500 -250 = 250

Help show the work for
5.2 divide by 0.13

Answers

Answer:

40

Step-by-step explanation:

0.13 ⟌5.2 (We can move 0.13 over two spots)

13⟌520 (We move the decimal two spots because of previous)

We have

    ₄ ₀

13⟌520

  - 52

______

      0 0

       - 0

   ______

          0

So 40 is our final answer.

The value of  (5.2/0.13) is 40 obtained by removing the decimals.

What are some alternative names for arithmetic operations?

Addition is also known as the sum, subtraction is also known as the difference, multiplication is also known as the product, and division is also known as the factor.

Given, 5.2 is divided by 0.13, which is (5.2/0.13).

Now we can multiply both the numerator and the denominator by 100.

(5.2/0.13)×(100/100).

= 520/13.

= 40.

learn more about decimal division here :

https://brainly.com/question/3004071

#SPJ2

15^1/5 rewrite in radical form

Answers

Answer:

[tex]\sqrt[5]{15}[/tex]

Step-by-step explanation:

A number to 1/5 is the [tex]\sqrt[5]{n}[/tex]

A number to 1/3 is the [tex]\sqrt[3]{n}[/tex]

So, since the number is 15 to the 1/5, it is [tex]\sqrt[5]{15}[/tex]

Answer:  [tex]\sqrt[5]{15}[/tex]

Answer:

[tex]15^{\frac{1}{5} } = \sqrt[5]{15}[/tex]

Step-by-step explanation:

recall that

[tex]a^{\frac{1}{b} } = \sqrt[b]{a}[/tex]

if we apply this to our case,

[tex]15^{\frac{1}{5} } = \sqrt[5]{15}[/tex]

Ben is 12 years older than Ishaan.Ben and Ishaan first met two years ago.Three years ago,Ben was 4 times as old as Ishaan.

Answers

Ben is 19 and Ishaan is 7.

If 3 years ago Ben was 4 times the age of Ishann, their ages could have been any of the following:

1. Ben is 4 and Ishaan is 1

2. Ben is 8 and Ishaan is 2

3. Ben is 12 and Ishaan is 3

4. Ben is 16 and Ishaan is 4

And so on.

Next add 3 to both ages, to show current age.

1. Ben is 7 and Ishaan is 4

2. Ben is 11 and Ishaan is 5

3. Ben is 15 and Ishaan is 6

4. Ben is 19 and Ishaan is 7

Ben is currently 12 years older than Ishaan. To find the difference, take Ben's age and subtract Ishaan's age.

1. 7 - 4 = 3

2. 11 - 5 = 6

3. 15 - 6 = 9

4. 19 - 7 = 12

Thus meaning Ben is 19 and Ishaan is 7.

I hope this helps!

Eric bought apples and oranges for $7.75. He paid $2.35 for all the apples
and $0.45 for each orange. How many oranges did he buy?

Answers

Answer:

He bought 12 oranges.

Step-by-step explanation:

Key words: "ALL the apples" "EACH orange."

7.75-2.35= 5.4

5.4/0.45= 12

Answer:

He bought 12 oranges.

Step-by-step explanation:

Keywords: "ALL the apples" and "EACH orange."

7.75-2.35= 5.4

5.4/0.45= 12

Step-by-step explanation:

how to graph -5x + y = 1

Answers

Answer:

look on the graph i gave you

Step-by-step explanation:

Multiplying Polynomials, Simplify with Work Shown.

3x^2 (4x^3 + 9x^2 - 8x + 4)

20 Point offer for real, complete answer.

Answers

Answer:

12x^5+27x^4-24x^3+12x^2:

Step-by-step explanation:

hope it helps

Solve -8(2z-3) Equivalent to -16z-3

Answers

Answer:

-16z + 24

Step-by-step explanation:

Apply the Distributive Property of Multiplication:

-8(2z-3) = -16z + 24

Answer:

-27

Step-by-step explanation:

-8 ( 2z - 3 ) = -16z - 3

distribute -8

-16z + 24 = -16z - 3

add 16z on right side

z + 24 = - 3

subtract 24 on left side

z = -27

Hopefully this helps :)

A central angle of a sector equals 5 radians and the radius equals 20 inches. What is the measure of the arc length formed by the sector?

Answers

Answer:

100

Step-by-step explanation:

What is the area of the frame around the picture?

Answers

12 x 6s - 8 x 4s = 72s - 32s = 40s

Answer:

40s units²

Step-by-step explanation:

Area of frame = area of bigger rectangle - area of smaller one

Area of big rectangle = length × breadth

= 12 × 6s = 72s unit²

Area of smaller rectangle = length x breadth

= 8 × 4s = 32s units²

Area of frame  = 72s -  32s

= 40s units²

I hope this was helpful, please mark as brainliest

Find the value of x to the nearest tenth.

Answers

Answer:

16. The answer is 16.5

17. The answer is Sin33.1°

18. The answer is 38.2

Step-by-step explanation:

In rounding up figures, number 1 to 4 is rounded up to 0 while numbers 5 to 9 is rounded up to 1.

16. Two sides in the right angle triangle are involved, the opposite side and the adjacent side, hence we use the tangent.

Tan36°=12/x

Cross multiply

x(tan 36°)= 12

Divide both sides by tan36°

x= 12/tan36°

16.516583

Rounded to the nearest tenth, we have 1 as the digit hundredth, which will be rounded up to 0.

Added to the tenth digit, still remains 5.

Answer therefore is 16.5

17. Two affected sides here is the opposite side and hypothenus sid, hence we use the sine.

sin x=12/22

= 33.055°

The digit hundredth is 5, which is rounded up to 1. Added to the tenth digit, we have 0+1=1

Answer is 33.1

18. Two affected sides are the opposite side and hypothenus side, we also use the sine.

Sin58°=x/45

Make x the subject

x=45/sin58°

38.162

6 is the digit hundredth, and it is rounded up to 1. Adding 1 to 1, the tenth digit in the figure above, we have our answer as

38.2

A shoreline is eroding at a rate of 1/3 foot per 3 months. How many feet are eroding per year?

Answers

The number of feet the shoreline is eroding per year is 1 ⅓ feet.

How many feet are eroding per year?

Rate of shoreline eroding per 3 months = 1/3 foot

Number of 3 months in a year = 12 months / 3 months

= 4

Number of feets of the shoreline eroding per year = Rate of shoreline eroding per 3 months × Number of 3 months in a year

= 1/3 × 4

= 4/3 feet per year

Therefore, the shoreline erodes 1⅓ feet per year

A local hamburger shop sort of combined total of 724 hamburgers and cheeseburgers on Tuesday there were 74 more cheeseburgers sold them hamburgers how many hamburgers were sold on Tuesday

Answers

Answer:

325

Step-by-step explanation:

h + 74 = 724

h = 724 - 74

h = 650.

h = 325.

The circle is inscribed in triangle PRT. A circle is inscribed in triangle P R T. Points Q, S, and U of the circle are on the sides of the triangle. Point Q is on side P R, point S is on side R T, and point U is on side P T. The length of R S is 5, the length of P U is 8, and the length of U T is 6. Which statements about the figure are true? Select two options. The perimeter of the triangle is 19 units. TU ≅ TS PU ≅ TU The length of line segment PR is 13 units. The length of line segment TR is 10 units.

Answers

Option B: [tex]TU $\cong$ TS PU $\cong$ TU[/tex]

Option C: The length of line segment PR is 13 units.

Explanation:

Given that the circle is inscribed in triangle PRT. Points Q, S, and U of the circle are on the sides of the triangle. Point Q is on side P R, point S is on side R T, and point U is on side P T.

The length of RS is 5, the length of PU is 8 and the length of UT is 6.

Option A: The perimeter of the triangle is 19 units.

The perimeter of the triangle is given by

Perimeter of ΔPRT = PU + UT + TS + SR + RQ + QP

Since, P, T and R are tangents to the circle and we know that "Tangents to a circle drawn to a point outside the circle are equal in length".

Thus, we have,

RS = RQ = 5

PU = PQ = 8 and

UT = TS = 6

Substituting the values in the perimeter of ΔPRT, we get,

Perimeter of ΔPRT = 8 + 6 + 6 + 5 + 5 + 8 =38 units

Thus, the perimeter of the triangle is 38 units.

Hence, Option A is not the correct answer.

Option B : [tex]TU $\cong$ TS PU $\cong$ TU[/tex]

Since, P, T and R are tangents to the circle and we know that "Tangents to a circle drawn to a point outside the circle are equal in length".

Then [tex]TU $\cong$ TS PU $\cong$ TU[/tex]

Hence, Option B is the correct answer.

Option C: The length of line segment PR is 13 units.

The length of PR is given by

PR = PQ + QR

Substituting the values RQ = 5 and PQ = 8, we get,

PR = 5 + 8 = 13 units

Thus, the length of line segment PR is 13 units.

Hence, Option C is the correct answer.

Option D: The length of line segment TR is 10 units.

The length of TR is given by

TR = TS + SR

Substituting the values TS = 6 and SR = 5, we get,

TR = 6 + 5 = 11 units

Thus, the length of line segment TR is 11 units

Hence, Option D is not the correct answer.

Answer: b and e

Step-by-step explanation:

owl is related to a mouse in the same way that a predator is related to​

Answers

Answer:

its prey

Step-by-step explanation:

An owl is a predator to a mouse, they attack mice and eat them so the owl is the predator and the mouse is the prey. There for an owl is related to a mouse in the same way that a predator is related to its prey

Yo sup??

the answer to this question is prey

as an owl eats a mouse similarly a predator eats is prey

Hope this helps

You buy a watch for $60. Your friend buys the same watch a month later. It is now sold at a discount of 15%. What is the new sale price?

Answers

Answer:

$9.00

Step-by-step explanation:

                                     ~~~~Hey there~~~~

1. Since it was 15% discount, that means you have to solve 15% of 60, which is equivalent to 0.15 x 60.

2. Since the product of 0.15 and 60 is 9, then 9 is your answer.

3. Your final answer is $9.00

Hope this helped!

~delightedsunrise8

Answer:

56

Step-by-step explanation:

You would first do 60 divide by 15 and get 4. Then you subtract 4 from 60 and get 56 as your answer.

Coach Jericho recorded the number of shots made by the starters on the 6th grade and 8th grade boys’ basketball team during the season.

6th Grade 8th Grade
22, 15, 17, 18, 20 58, 58, 52, 55, 53


Which statement is true? Select two answers.

A.
The data spread for the 8th graders is greater than for the 6th graders.

B.
Both sets of data have the same mean.

C.
The data set distribution for the 6th grade players is skewed right.

D.
The mean for the 8th grade players is 3 times the mean for the 6th grade players.

E.
The data set distribution for the 8th grade players is symmetric.

Answers

Answer:

D. The mean for the 8th grade players is 3 times the mean for the 6th grade players. & E. The data set distribution for the 8th grade players is symmetric.

What’s 4(-8x+5)-(33x-26)=

Answers

Answer:

x = -6/65

Step-by-step explanation:

Perform the indicated multiplications:  4(-8x+5) - 1(33x-26), obtaining:

-32x + 20 - 33x + 26

Combining like terms, we get

-65x = 6, or

x = -6/65

suppose you connect the points on the graph in the example, what would the graph look like?

Answers

Answer:

Your graph would look like lines going up and up and up

Step-by-step explanation:

Why you ask? Well, because the graph shown here is going by the factors of 6. And the factors of 6 are pretty high, which means it would be going up like a twisted line going right ot left depending which way you look at it. It would be going up and up because like 18 times 6 is 108 and 20 times 6 is 120.

WILL GIVE 100 POINTS,.A car’s wheels spin at 1000 revolutions per minute. The diameter of the wheels is 23 inches. You want to know how fast the car is travelling. Show your work

Answers

Answer:

72,220

Step-by-step explanation:

23,000 • 3.14 =

If the vehicle is traveling at 1,000 revolutions per minute, with the diameter of the wheels being 23 inches, the vehicle would be moving at 72,220 inches per minute.

72220.000512 = 68.390152 = 68 MPH

PLEASE be respectful and don't do this for the points!

At the mission museum Mrs. Perez visited over break, there is a pond like the one below that has a ring-shaped sidewalk around it. The outer edge of the sidewalk is a circle with a radius of 10 m. The inner edge of the sidewalk is a circle with a radius of 8 m.
(a) Write and simplify an expression for the exact area of the sidewalk. (4 points possible)
(b) Find the approximate area of the sidewalk. Use 3.14 to approximate π. (3 points possible)

Answers

Answer:

The formula for area of a circle is : A = PI x r^2

A) find the are of the two circles, subtract the two to find the area of the side walk:

Outside circle: A = PI x 10^2

Area = 100PI

Inner circle: A = PI x 8^2

Area = 64PI

Area of sidewalk:

100PI - 64 PI = 36PI

B) replace PI with 3.14:

Area = 36 x 3.14 = 113.04 square meters.

Step-by-step explanation:

Hope this helped.

Decimal equivalent to 11/44

Answers

Answer:0.25

Step-by-step explanation:

11/44 is equal to 1/4

1/4 is 0.25

Which is true regarding Adi's use of algebra tiles?

Adi used algebra tiles to represent the product

(-2x-2)(2x-1).

A. She used the algebra tiles correctly.

B. She did not represent the two original factors correctly

on the headers.

C. The signs on some of the products are incorrect.

D. Some of the products do not show the correct powers

of x.

Answers

Answer:

A. True

B. False

C. False

D. False

Step-by-step explanation:

Hence she used it correctly by making parts of it.

Answer: Its A my boy

Step-by-step explanation:

it take 96 pounds or seed to completely plant a 10-acre field. how many pounds of seed are needed per acre?

Answers

Answer:

9.6 lb/acre

Step-by-step explanation:

This is a unit rate problem. You want to know the number of pounds used for one acre.

You divide 96 pounds by 10 acres to find the number of pounds per 1 acre.

(96 lb)/(10 acres) = 9.6 lb/acre

Answer: 9.6 lb/acre

Final answer:

To find how many pounds of seed are needed per acre, divide the total amount of seed used, which is 96 pounds, by the total area, 10 acres. The answer is 9.6 pounds per acre.

Explanation:

This problem is a simple division problem in Mathematics. We start by taking the total amount of seed that was used, which is 96 pounds. Then, we divide this by the total area, which in this case is 10 acres.

When we perform the calculation: 96 pounds ÷ 10 acres, the solution we get is 9.6 pounds per acre.

So, it requires 9.6 pounds of seed to plant one acre of the field. Remember, this is an average estimation. Actual seed requirement may vary depending on the type of seed and other factors such as soil and weather conditions.

Learn more about Division here:

https://brainly.com/question/33969335

#SPJ2

7. (03.05 LC)
The functions f(x) and g(x) are described below:
f(x) = 7x + 9
g(x) = 7x – 4
The graph of g(x) is obtained by shifting down the graph of f(x) byl
units. (5 points)
8. (03.05 LC)
T
halha
t atamata baze decrribae the Affert frankmino thaiarnik
r.​

Answers

Answer:

13 units

Step-by-step explanation:

g(x) = 7x + 9 - 13

g(x) = f(x) - 13

Answer:

7.       the answer is 13

Step-by-step explanation:

Please answer ASAP! Thank you in advance and make sure to use antibacterial soap and wash your hands for 1 minute.

Answers

Answer:

[tex]12.5 \ ft^2[/tex]

Step-by-step explanation:

Given that height is a quarter the sum of bases and that the height is 2.5ft.

The sum of bases is calculated as:

[tex]h=\frac{1}{4}\sum{b_i}=2.5\\\\\sum{b_i}=2.5\times 4\\\\\sum{b_i}=b_1+b_2=10\ ft[/tex]

#Having that (b1+b2=10 ft), we can now calculate the area using the given formula using the given figures:

[tex]A=\frac{1}{2}\times 2.5\times (b_1+b_2), b_1+b_2=10\\\\=\frac{1}{2}\times 2.5\times10\\\\=12.5[/tex]

Hence, the area of the trapezoid is 12.5 sq ft

*Using the h=2.5ft and the [tex]A=\frac{1}{2}h(b_1+b_2)[/tex]

Other Questions
If a sexually reproducing organism has 28 chromosomes in its body cells, how many chromosomes did it inherit from each parent? What is the connection between the men of the whaleshipEssex and the audience Walker is addressing? Trial 1, H H T; trial 2, H T T; trial 3, H H T; trial 4, H H H; trial 5, H H T; trial 6, H H T; trial 7, T T T; trial 8, H H T; trial 9, H T T; trial 10, H H H; trial 11, H H T; trial 12, T T T; trial 13, T T T; trial 14, H T T; trial 15, H T T; trial 16, T T T; trial 17, H H T; trial 18, H T T; trial 19, H T T; trial 20, H T T.On a nearby pond, black and white ducks are swimming in groups of three. Use the table to find the experimental probability of two white ducks and one black duck swimming together. Tails up represents white ducks and heads up represents black ducks. Morgan Bowie is trying to determine the amount to set aside so that he will have enough money on hand in 3 years to overhaul the engine on his vintage used car. While there is some uncertainty about the cost of engine overhauls in 3 years, by conducting some research online, Morgan has developed the following estimates.Engine Overhaul Estimated Cash Outflow Probability Assessment $390 10% 570 30% 750 50% 790 10%How much should Keith Bowie deposit today in an account earning 6%, compounded annually, so that he will have enough money on hand in 6 years to pay for the overhaul? Recall that last year the overall printing costs were $2.31 per calendar, totalling $19,183. Max is very disappointed to learn that printing costs for the calendars are going to be higher this year. The unit cost per calendar will be $2.45. If Max prints only the number of calendars that he projects to be sold, what do you project overall calendar profits to be this year (assuming he sells them for the same price as last year Consumer complaints are frequently reported to the Better Business Bureau. Industries with the most complaints to the Better Business Bureau are often banks, cable and satellite television companies, collection agencies, cellular phone providers, and new car dealerships. The results for a sample of 200 complaints are in the file BBB.(a) Show the frequency and percent frequency of complaints by industry.Industry Frequency % Frequency Bank Cable Car Cell Collection Total (b) Which industry had the highest number of complaints?(c) Comment on the percentage frequency distribution for complaints. Contracts for sale may contain sections that cause implementation of the contract to depend on the successful completion of some prior action such as the buyer's ability to obtain financing on specified terms. This type of contract is commonly referred to as __________. Potential presidential candidates examine whether they have the ability to garner enough resources, both human and financial, to run a viable campaign and explore the viability of their success by participating in activities within what is often referred to as _____. Denber Co. acquired 60% of the common stock of Kailey Corp. on September 1, 2019. For 2019, Kailey reported revenues of $810,000 and expenses of $630,000, not including its investment in Denber, and all reflected evenly throughout the year. The annual amount of amortization related to this acquisition was $15,000. What is the amount of the noncontrolling interest's share of Kailey's income for 2019?a. $72,000.b. $22,000.c. $66,000.d. $24,000.e. $48,000. This system has one solution.y=8x+9y=x2+4x+13What is the y-coordinate of the solution?Enter your answer in the box. Which of the following is a fossil fuel?A) waterB) gasoline C) carbon dioxide D) ice A wire of length L is wound into a square coil with 167 turns and used in a generator that operates at 60.0 Hz and 120 V rms value in a 0.041-T magnetic field. What is the length L of the wire used to construct the coil Which job would most likely be paid salary plus commission? During the opening of the film Casablanca, we hear an airplane approaching and see people looking up at the sky; in the next shot, we see the airplane flying overhead. What continuity editing technique is primarily at work here? In one experiment, White respondents typically took longer to identify words such as peace and paradise as "good" when the words were associated with Black-sounding names rather than White-sounding names. This best illustrated:_______. At December 31, 2016, Teal Corporation had the following stock outstanding. 10% cumulative preferred stock, $100 par, 108,560 shares $10,856,000 Common stock, $5 par, 4,041,000 shares 20,205,000 During 2017, Teal did not issue any additional common stock. The following also occurred during 2017. Income from continuing operations before taxes $22,700,000 Discontinued operations (loss before taxes) $3,255,000 Preferred dividends declared $1,085,600 Common dividends declared $2,230,000 Effective tax rate 35 % Compute earnings per share data as it should appear in the 2017 income statement of Teal Corporation. (Round answers to 2 decimal places, e.g. 1.48.) Whatever the reason, a swell of approval palpable as rain lifted from the center of the crowd and rolled out toward its edges, where it crashed against buildings and water wall and rolled back at Scotty with redoubled force, lifting him off his stool, onto his feet (the roadies quickly adjusting the microphones), exploding the quavering husk Scotty had appeared to be just moments before and unleashing something strong, charismatic, and fierce. Anyone who was there that day will tell you the concert really started when Scotty stood up. How does the author portray Scotty in this excerpt? Will mark brianliest!! asap due today!!!write in your own words pleaseDescribe 2 steps for warming up and 2 steps for cooling down. The idea in Exercise 3.51 generalizes to give a new formula for the expected value of any nonnegative integer-valued random variable. Show that if the random variable X takes only nonnegative integers as its values then E(X) = X[infinity] k=1 P(X k). This holds even when E(X) = [infinity], in which case the sum on the right-hand side is infinite. Hint. Write P(X k) as P[infinity] i=k P(X = i) in the sum, and then switch the order of the two summations. What is the most critical principle for non-Pakistanis to understand about how Pakistan views its neighbors? Why is this principle important to understand?