To increase the area of circle by 44% by what percent should its radius incresed
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let radius=r
let %increase=p%
new radius=r+pr/100
area =pi* r^2
new area=pi*(r+pr/100)^2
=pi*(r^2+p^2r^2/10000+2pr^2/100)
44=(p^2r^2/10000+2pr^2/100)*100/r^2
44=(p^2/100+2p)
p^2+200p-4400=0
(p+220)(p-20)=0
p=20%
let %increase=p%
new radius=r+pr/100
area =pi* r^2
new area=pi*(r+pr/100)^2
=pi*(r^2+p^2r^2/10000+2pr^2/100)
44=(p^2r^2/10000+2pr^2/100)*100/r^2
44=(p^2/100+2p)
p^2+200p-4400=0
(p+220)(p-20)=0
p=20%
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