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To increase the area of circle by 44% by what percent should its radius incresed |
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Answer» 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% |
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