每日一题

Mathematics

Adolfo wants to send his friend a rectangular poster with a width of 65 centimeters(cm) and a length of 92cm. He will mail the poster in a container in the shape of a right circular cylinder with a volume of 5200 cubic centimeters(cm^3). The height of the container is the same as the width of the poster. Which of the following is closest to the largest radius the container could have?

A.4cm
B.5cm
C.8cm
D.25cm

答案和解析

答案：B

解析：

Choice B is correct.

The volume of a right circular cylinder of radius r and height h is V=πr^2h.

To satisfy the conditions, V≤5200 must be true:

πr^2(65)≤5200

r≤25.4647

If r≤5 centimeters, the volume will not exceed 5200cm^3.

The largest listed radius that satisfies the volume constraint is 5cm.