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2 years ago

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A school replaced 20% of it computers with new ones . what the total number of computers in the school if 55 computers were repl

aced?

1 answer:

sladkih [1.3K]2 years ago

7 0

The total is 275 because 100% divided by 20% is 5 and if 20%= 55 then that means that 55 goes into 100% 5 times so you multiply 55 by 5 to get 275. Hope I helped! Please rate me as the brainliest!

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Chandresh is helping his father paint the fence in their back yard. The fence is represented by the shaded part of the diagram b

Lyrx [107]

B. The total area painted is 864; they must buy two cans of paint.

Step-by-step explanation:

Step 1:

A rectangle's area can be calculated by multiplying its length and its width. The wall is made up of 5 different types of rectangular walls. All walls are 8 feet tall but the length varies.

Step 2:

The area of the 20 feet long wall = $(length)(width)= (20)(8) =160,$

The area of the 10 feet long wall = $(length)(width)= (10)(8) =80,$

The area of the 5 feet long wall = $(length)(width)= (5)(8) =40,$

The area of the 4 feet long wall = $(length)(width)= (4)(8) =32,$

The area of the 15 feet long wall = $(length)(width)= (15)(8) =120.$

The area of all the walls = 432 square feet.

Since there are two sides for every wall, total area = $432(2)=864$ square feet.

Step 3:

If one paint can covers 500 square feet,

the number of cans required to paint 864 square feet = $\frac{864}{500} = 1.728$ cans.

so 2 paint cans are needed to paint 864 square feet which is option B.

7 0

2 years ago

The sun subtend an angle at 35degree from the centre of the earth whose distant from the centre of the earth is 382,100km. Find

Sonbull [250]

Study the figure attached below:

Answer:

240951.33km

Step-by-step explanation:

For this type of question first we need to draw the figure as shown in the attached file (Figure.1).

Looking at the figure, we can see that triangle ABC is formed by bisecting the angle 35 degree (i.e. if the angle is bisected, it will divide into two equal parts, so 35 degree will divide into two equal parts of 17.5 degree).

As the triangle ABC is a right triangle, so we can use the trigonometric ratios to find the diameter of the sun.

$tan(\theta )= \frac{perpendicular}{Base}$

In the triangle ABC, perpendicular (opposite side to $\theta$ ) is BC and base (Adjacent side) is AC

$tan(\theta)=\frac{BC}{AC}$

$\theta$ =17.5 degree

AC=382100km

Putting the values, we get

$tan(17.5)=\frac{BC}{382100}\\ \\BC=tan(17.5)*382100km\\\\BC=0.315*382100km\\\\BC=120475.66km$

Diameter=d=2*Radius

As BC is the distance from center of the sun, it is the radius, so we can find the diameter if we multiply it by 2.

Diameter of the sun=d=2*120475.66km

$The\ diameter\ of\ the\ sun\ = 240951.33km$

7 0

2 years ago

Read 2 more answers

Pirate Jack has an equal number of gold and silver coins. If Pirate Jack splits all of his coins into 7 equal piles for his parr

Kipish [7]

Answer:

The least possible number of coins that Pirate Jack has is 77.

Step-by-step explanation:

i) let the number of coins in the piles for the parrots be x.

ii) therefore we can say that the total number of coins be 7x + 4

iii) let the number of coins in the piles for for the pirates be y.

iv) therefore we can say that the total number of coins be 11y + 4

v) therefore we can say that 7x + 4 = 11y + 4

vi) therefore 7x = 11y

vii) therefore the least possible number of coins that Pirate Jack has is equal to the LCM of 11 and 7 which is 77.

viii) x = 11 and y = 7

3 0

2 years ago

PLEASE I NEED HELP ASAP! The function below represents the interest Jessi earns on an investment. Identify the term that represe

luda_lava [24]

Answer:

1000

Step-by-step explanation!

The formula for the amount accrued [ƒ(x)] on an investment earning compound interest is f(t) = P(1 + r)^t where:

P = the amount of money invested (the principal)

r = the interest rate per payment period expressed as a decimal fraction

t = the number of periods

Your formula is

f(x) = 1000(1 + 0.05)^x

In comparison, we can see that the term that represents the amount of money originally invested is 1000.

6 0

2 years ago

Read 2 more answers

Tatooine is a fictional desert planet that appears in the Star Wars franchise. It is home to many settlers, including humans. Le

Dovator [93]

Answer:

a) For this case we select a sample size of n =9. And the distribution for the sample mean is given by:

$\bar X \sim N (\mu , \sqrt{\frac{\sigma}{\sqrt{n}}})$

With the following parameters:

$\mu_{\bar X}= 96$

$\sigma_{\bar X} = \frac{23.3}{\sqrt{9}} =7.767$

b) $P(95< \bar X < 100)$

And we can use the z score formula given by:

$z = \frac{\bar X -\mu}{\frac{\sigma}{\sqrt{n}}}$

And if we find the z score for the limit we got:

$z = \frac{95-96}{\frac{23.3}{\sqrt{9}}}= -0.129$

$z = \frac{100-96}{\frac{23.3}{\sqrt{9}}}= 0.515$

$P( -0.129 < Z< 0.515) = P(Z$

The sketch is on the figure attached

Step-by-step explanation:

Previous concepts

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".

Solution to the problem

Let X the random variable that represent the weights of a population, and for this case we know the distribution for X is given by:

$X \sim N(96,23.3)$

Where $\mu=96$ and $\sigma=23.3$

Part a

For this case we select a sample size of n =9. And the distribution for the sample mean is given by:

$\bar X \sim N (\mu , \sqrt{\frac{\sigma}{\sqrt{n}}})$

With the following parameters:

$\mu_{\bar X}= 96$

$\sigma_{\bar X} = \frac{23.3}{\sqrt{9}} =7.767$

Part b

For this case we want this probability:

$P(95< \bar X < 100)$

And we can use the z score formula given by:

$z = \frac{\bar X -\mu}{\frac{\sigma}{\sqrt{n}}}$

And if we find the z score for the limit we got:

$z = \frac{95-96}{\frac{23.3}{\sqrt{9}}}= -0.129$

$z = \frac{100-96}{\frac{23.3}{\sqrt{9}}}= 0.515$

$P( -0.129 < Z< 0.515) = P(Z$

The sketch is on the figure attached

3 0

2 years ago