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2 years ago

How do I solve this problem?

Mathematics

1 answer:

natulia [17]2 years ago

5 0

Step-by-step explanation:

you know the formulas ?

the area of a circle is : pi×r²

the circumference of a circle is : 2×pi×r

with r being the radius, which is half of the diameter.

so, here, r = 10/2 = 5 m

area = pi×r² = pi×5² = pi×25 or 25×pi m²

circumference = 2×pi×r = 2×pi×5 = 10×pi m

for the approximation we make the calculations with pi on the calculator and round to the nearest hundredth.

area = 25×pi ≈ 78.54 m²

circumference = 10×pi ≈ 31.42 m

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The line representing a proportional relationship always goes through the point (0,0). If x is zero, multiplying x by the consta

Sidana [21]

Answer:

B (2, 4)

Step-by-step explanation:

we know that

A relationship between two variables, x, and y, represent a proportional variation if it can be expressed in the form $k=\frac{y}{x}$ or $y=kx$

In a proportional relationship the constant of proportionality k is equal to the slope m of the line and the line passes through the origin

In this problem the constant of proportionality k is given and is equal to

$k=2$

The linear equation is given by

$y=2x$

That means ----> the y-coordinate is two times the x-coordinate

therefore

The other point is B(2.4)

Because

For x=2, y=4

the y-coordinate is two times the x-coordinate

$4=2(2)\\4=4$

3 0

3 years ago

here are 1515 people in an office with 55 different phone lines. If all the lines begin to ring at once, how many groups of 55 p

Mashcka [7]

Answer:

360,360 groups of 5 people.

Step-by-step explanation:

We have been given that there are 15 people in an office with 5 different phone lines. We are asked to find groups of 5 people that can answer these lines, if all the lines begin to ring at once.

We will use fundamental principle of counting to solve our given problem.

There are 15 people to answer 1st line, that will leave us with 14 people to answer 2nd line.

Now, we will have 13 people to answer 3rd line, that will leave us with 12 people to answer 4th line.

There are 11 people to answer 5th call.

So 5 lines can be answered in $15\times 14\times 13\times 12\times 11=360,360$ ways.

Therefore, 360,360 groups of 5 people can answer these lines.

6 0

3 years ago

Two numbers are in the ratio 7:9 if the sum of the number is 112 then the lrger number is?

nordsb [41]

Answer:

Step-by-step explanation:

the numbers are in ratio 7 : 9 = 7x : 9x ( x is a multiplier )

given the sum of the numbers = 112 , then

7x + 9x = 112 , that is

16x = 112 ( divide both sides by 16 )

x = 7 , then

9x = 9 × 7 = 63 ← value of larger number

7 0

1 year ago

A city has 3 new houses for every 9 old houses. If there are 15 new houses in the city, how many old houses are there?

Arisa [49]

Answer:

45 old houses

Step-by-step explanation:

new houses : old houses

3 : 9

15 : ?

(3 = 1st ratio and 9 = 2nd ratio)

To find the missing ratio, divide the first ratio from the new ratio:

15 / 3 = 5

Take the product and multiply that by the second ratio to find the missing ratio:

9 x 5 = 45

6 0

2 years ago

Read 2 more answers

Julie and Eric row their boat (at a constant speed) downstream for 40 miles in 4 hours, helped by the current. Rowing at the sam

Liula [17]

Answer: 3 miles per hour

Step-by-step explanation:

Use the formula "distance (d) = rate (r) x time (t)" to create a system of equations.

Let "r" represent the rate they are rowing

Let "c" represent the current

time rate distance EQUATION

Downstream: 4 hours r + c 40 miles 4(r + c) = 40

Upstream: 10 hours r - c 40 miles 10(r - c) = 40

Distribute, then eliminate r to solve for c:

Down: 4r + 4c = 40 → 5(4r + 4c = 40) → 20r + 20c = 200

Up: 10r - 10c = 40 → -2(10r - 10c = 40) → -20r + 20c = -80

40c = 120

÷40 ÷40

c = 3

4 0

2 years ago

How do I solve this problem? ​

How do I solve this problem?