Question

This is a related rates problem [calculus 1]
A fire has started in a dry, open field and spreads in the form of a circle. The radius of the circle increases at the rate of 6ft/min. Find the rate at which the fire is increasing when the radius is 150 feet.

Answer 1

whats the formula for the area of a circle

Answer 2

no pain, no gain

Answer 3

a=pie r^2

Answer 4

\[A=pir ^{2}\]
d/dt[A]=d/dt[pi r^2]

Answer 5

dA/dt=2 pi r(dr/dt)

Answer 6

Do you follow so far?

Answer 7

dA/dt = (2) (Pi) (150) (6)
Your answer will be in square ft per minute.

Answer 8

yes

Answer 9

5,655 sq ft/min

Answer 10

Seem like it is spreading pretty fast, maybe someone else can verify this answer.