A rectangular sheet of paper of length 35 cm and breadth 28 cm is folded in two ways to form a cylinder. Find the difference in the volumes of cylinders formed.
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A rectangular sheet of paper of length 35 cm and breadth 28 cm is folded in two ways to form a cylinder.

Difference between volume

At first

Way 1

Let's take height as breadth and Length as circumference

35 = 2 × 22/7 × r

35 × 7 = 2 × 22 × r

245 = 44r

245/44 = r

4.5 cm ≈ r

Now,

Volume = πr²h

Volume = 22/7 × 5.5² × 28

Volume = 22/7 × 30.25 × 28

Volume = 22 × 30.25 × 4

Volume = 2662 cm²

Way 2

Lets take Length as height and Breadth as circumference

28 = 2 × 22/7 × r

28/2 = 22/7 × r

14 = 22/7 × r

14 × 7/22 = r

4.4 = r

Now,

Volume = πr²h

Volume = 22/7 × 4.4² × 35

Volume = 22/7 × 19.36 × 35

Volume = 22 × 19.36 × 5

Volume = 2130 cm²

Now,

Difference = 2662 - 2130

Difference = 532 cm

Area of Circle = πr²

TSA of cuboid = 2(lb + bh + lh)

CSA of cuboid = 2h(l + b)

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