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प्रश्न
The diameter of a garden roller is 1.4 m and it is 2 m long. How much area will it cover in 5 revolutions? (Take π = 22/7)
उत्तर
Clearly, Area covered = Curved surface area x No. of revolutions
Here, r = `1.4/2` m = 0.7 m and h = 2 m
∴ Curved surface area = 2πrh
= 2 x `22/7` x 0.7 x 2 m2
= 8.8 m2
Here, Area covered = 8.8 m2 x 5 = 44 m2.
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