Question

if the radius of the circle is increased by 10% then the area is increased by?

Answer 1

The relation between Area and radius is A= pie r^2

Answer 2

Original area = pi r^2

New area = pi (r *1.1)^2 = pi r^2 *1.1^2

so divide the new by th eold to find the increase in area

Answer 3

why its 1.1?

Answer 4

the answer must be
2.1%
21%
121%
none of these

Answer 5

Why it is 1.1 instead of 0.1 @MrNood ? I think it should be 0.1.

Answer 6

exactly it should be 0.1

Answer 7

@AnswerMyQuestions

Answer 8

Not so sure about this.

Answer 9

the above post is correct

Answer 10

how?

Answer 11

The new radius is equal to the old radius + .1(of the old radius) so

New Radius= r + .1r= 1.1 r

Answer 12

(pi * (1.1*r)^2 ) / ( pi * r^2)

Answer 13

ok whats the answer then?

Answer 14

1.1^2 = 1.21

Answer 15

New Radius= r + .1r= 1.1 r didnt get this step

Answer 16

r + 10% * r

Answer 17

why we plus r

Answer 18

since you want to increase r

Answer 19

ok

Answer 20

if i have a 100 dollars, and i want to increase by 10%

100 + 10% * 100

Answer 21

If you have 30 dollars and I give you 10 % 0f 30 =.1 (30)=3 dollars , the you will have 30+3=33= 1.1 (30)

Answer 22

so in general, the formula is

initial amount + (percentage increase) * initial amount

Answer 23

ok

Answer 24

so here we have r + 10%*r , or r + .10 * r

Answer 25

yeh the answer is 121%?

Answer 26

@perl

Answer 27

yes, the area is increased by 121 %

Answer 28

alternatively, by a factor of 1.21

Answer 29

Thanks @perl for the logic :)

Answer 30

your welcome

Answer 31

ty:)

Answer 32

eliasaab also deserves credit

Answer 33

yeh thanks @eliassaab

Answer 34

@eliassaab good explanation

Answer 35

Thanks @eliassaab :)