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mathematics

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If the radius of a circle is increased by 20% then the area is increased by how many percent?
 
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let radius of a circle = 10 cm
So the area of the circle =[ π ] x r ^2
22/7 x (10) ^ 2 = 314.16 Cm ^2

So when radius is 10 cm the Area is 314.16 Cm ^2

Now let's increase the radius 10 Cm by 20 %

20/100 x 10 = 2 cm

2 + 10 = 12 Cm

So the new radius ( by an increase of 20 % ) = 12 Cm

Now we can calculate the new area due to the New radius

Area = [ π ] x r ^2
= 22/7 x (12) ^ 2
= 452.39 Cm ^ 2

So With an radius of 12 Cm the new area is452.39 Cm ^ 2



to calculate how much percent the area is increased

452.39 / 314.16 x 100 = 144 %

144 % - 100 % = 44 %
therefore whenever the radius is increased by 20 % the area is Increased By 44 % :)


If you didnt get any point Do let Me know :)
 
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heyy 1 thing i want 2 knoww radius v have 2 SUPPOSE THE RADIUS
 
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Meesam said:
heyy 1 thing i want 2 knoww radius v have 2 SUPPOSE THE RADIUS

Yes !
You have to suppose any value of the radius , but whatever you take the Final Answer is Gonna be 44 % :)
 
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