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प्रश्न
A tent of height 8.25 m is in the form of a right circular cylinder with diameter of base 30 m and height 5.5 m, surmounted by a right circular cone of the same base. Find the cost of the canvas of the tent at the rate of Rs 45 per m2.
उत्तर
`l = sqrt((2.75)^2) + (15)^2`
`l = sqrt(232.5625)`
`= 15 .25`
Total surface area of the tent
`=2 pirh + pirl`
`=pir(2h + l)`
`=22/7 xx 15[2 xx 5 -5 + 15.25]`
`= (330 xx 26.25)/7`
`=1237.5`
Therefore,
Cost of the canvas of the tent
`=1237.5 xx 45`
`= "Rs . 55687.50"`
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