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प्रश्न
Find
How much steel was actually used, if `1/12` of the steel actually used was wasted in making the tank.
`["Assume "pi=22/7]`
उत्तर
Total surface area of tank = 2πr (r + h)
`=[2xx22/7xx(2.1+4.5)]m^2`
= (44 × 0.3 × 6.6) m2
= 87.12 m2
Let A m2 steel sheet be actually used in making the tank.
`therefore(1-1/12)=87.12m^2`
`rArr A=(12/11xx87.12)m^2`
⇒ A = 95.04 m2
Therefore, 95.04 m2 steel was used in actual while making such a tank.
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