A cylinder with a surface area of 50 square centimeters has a bottom area of 15 square centimeters. Two such cylinders form a large cylinder. What is the surface area of this large cylinder

A cylinder with a surface area of 50 square centimeters has a bottom area of 15 square centimeters. Two such cylinders form a large cylinder. What is the surface area of this large cylinder

Ruying 123,
The sum of the surface areas is:
50 × 2 = 100 (cm2)
Large cylinder surface area:
100-15 × 2 = 70 (cm2)