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2 years ago

The area of a circle is 81 ft 2 . What is the π circumference? Leave in terms of Pi.

Mathematics

1 answer:

KonstantinChe [14]2 years ago

7 0

Answer:

10.2π

Step-by-step explanation:

Given data

Area of circle= 81 ft^2

Also, the expression for the area of a circle is

A=πr^2

substitute

81=3.142*r^2

r^2= 81/3.142

r^2= 25.77

square both sides

r= √25.77

r= 5.1

Also, the expression for the circumference is

C= 2πr

substitute

C= 2*π*5.1

C= 10.2π

Hence the circumference is 10.2π

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Marco located the falllow points on a number line which point is not corrtly placed on the number line

mario62 [17]

Question:

Marco plotted the following points on the number line.

Point A: 0.3 Point B: 3/4 Point C: 11/4 Point D: 0.7

Which point did he plot incorrectly?

Answer:

Point D

Step-by-step explanation:

Given

$Point\ A= 0.3$

$Point\ B= \frac{3}{4}$

$Point\ C= \frac{11}{4}$

$Point\ D= 0.7$

Required

The incorrectly plotted point

Number plotted on a number line increases from left to right. This implies that:

$A < B < C < D$

Substitute the values for the given points

$0.3 < \frac{3}{4} < \frac{11}{4} < 0.7$

Express as fractions

$0.3 < 0.75 < 2.75 < 0.7$

Up till 2.75, the order of the numbers is correct.

However, 0.7 is less than 0.75 and 2.75

So, 0.7 is not placed correctly.

<em>This implies that point D is not correctly placed</em>

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3 years ago

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Vikki [24]

Answer:

Step-by-step explanation:

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3 years ago

If the difference between a number and 21 is divided by2, the result is 4 times the number. What is the number

Ostrovityanka [42]

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