The height and curved surface area of a right circular cylinder are 7 cm and 70 π cm2. Its total surface area is:
Answer & explanation
Correct answer: option 4
We know that,
Curved Surface Area = 2πrh
Total surface area = 2πr(r + h)
We have,
Height = 7 cm
Curved surface area = 70π cm2
= 2πr × 7 = 70π
= r = 5 cm
Now, Total surface area = = 2 × π × 5 × (5 + 7) = 120π cm2