The circumference of a circle is 25.12cm. What is the area of the circle? Use 3.14

1 answer:

3 0

C=2pir
area=pir^2

given
c=25.12
25.12=2pir
pi=3.14
25.12=2(3.14)r
25.12=6.28r
divide both sides by 6.25
4=r

sub into other
area=pir^2
area=pi4^2
area=16pi
area=16(3.14)
area=50.24

the area is 50.24 square cm

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room height is x feet
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Answer:

Rs 42000 and Rs 40000

Step-by-step explanation:

Given that Rs 82000 is divided into two parts.

Let the first part be Rs x which is compounded annually at the interest of 5% per annum for 2 years.

The rate of interest = 5%=0.05

The total amount after 2 years $= x(1+0.05)^{2}\cdots(i)$

The other part is Rs 82000-x which is compounded annually at the interest of 5% per annum for 3 years.

The total amount after 3 years $= (82000-x)(1+0.05)^{3}\cdots(ii)$

As both the amounts are equal, so from equation (i) and (ii)

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