This is urgent, my test is due in an hour, please help me solve this math problem?

Question

Air is being pumped into a spherical balloon at a rate of 10 cm3/min. Determine the rate at which the radius of the balloon is increasing when the diameter of the balloon is 25 cm.

SPQRALAN · Answer

diameter = 25 means radius = 12.5
volume at that radius = 4/3 pi*r^3 = 8181.2308

dV/dt = 10

V = 4/3 pi r^3
dV/dt = 4 pi r^2 dr/dt

plug in 10 for dV/dt and 12.5 for r

10 = 4 pi (12.5)^2 dr/dt

dr/dt = 0.00509 cm/s

This is urgent, my test is due in an hour, please help me solve this math problem?

1 Answer