a bucket is in the form of a frustum of a cone whose radii of bottom and top are 7 cm and 28 CM respectively if the capacity of the bucket is 21560 cm cube find the whole surface area of the bucket
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let the radii = r, R
r = 7cm ; R = 28cm
volume of bucket = 21560cm3
π/3 * h(r2 + R2 +rR) = 21560
22/21 * h (49 + 784 + 196) = 21560
h* 22*1029/21 = 21560
h = 21560/22 *21/ 1029
h = 20cm
l2 = h2 + (R -r)2
l2 = 400 + 441 = 841
l = 29 cm
SA of bucket = CSA + area of bottom
= πl(R + r) + πr2
= π(35 + 49) = 22/7 * 84
= 264 cm2
r = 7cm ; R = 28cm
volume of bucket = 21560cm3
π/3 * h(r2 + R2 +rR) = 21560
22/21 * h (49 + 784 + 196) = 21560
h* 22*1029/21 = 21560
h = 21560/22 *21/ 1029
h = 20cm
l2 = h2 + (R -r)2
l2 = 400 + 441 = 841
l = 29 cm
SA of bucket = CSA + area of bottom
= πl(R + r) + πr2
= π(35 + 49) = 22/7 * 84
= 264 cm2
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