Question

Find curved surface area and total surface of a cylinder when r = 7 and h = 12 cm

Answer 1

Explanation:

Curved surface area

=2πrh

=2π×12×7

=168π=168×

7

22

=24×22=528cm

2

Total surface area

=CSA+2πr

2

=528+2π×7×7

=528+(2×7×22)

=528+308=836cm

2

Answer 2

Answer:

Diameter =14 cm

Radius =7 cm

Height =15 cm

So,

TSA of cylinder =2πr(r+h)

=2×

7

22

×7(7+15)

=2×

7

22

×7×22

=968 cm

2

CSA of cylinder =2πrh

=2×

7

22

×7×15

=660 cm

2