R = 3.5 m
h = 12 m
slant height l = root of r2 + h2
= root of 3.5 square + 12 square
= 12.5 m
CSA = pi r l
= 22/7 * 3.5* 12.5
= 137.5 m2
let x m of cloth be required to make the tent.
thn CSA of conical tent = area of cloth.
5x = 137.5
therefore , x = 137.5 / 5
= 27.5 m
hence , 27.5 m cloth is required to make the conical tent.
HOPE IT CAN HELP:)