Dr /dt = 7
A = pi r^2
dA / dr = 2pir
dA/dt = dA/dr * dr/dt = 2pir * 7 = 14pir
when r = 12 rate of change of the area = 14*pi*12 = 168pi
= 527.79 cm^2 / minute to nearest hundredth
Answer:
6 is the answer bc 24/4 equals 6
Step-by-step explanation:
Wouldn't it be B ??? Hope this is right:) can you take a look at mine??
Given that the time taken to get to campus is inversely proportional to driving rate, let the time be t and rate be r, thus the function will be written as:'
t=k/r
where
k is the constant of proportionality given by:
k=tr
when r=20 mph, t=1.25 hrs
thus
k=20×1.25
k=25 miles
thus the formula is:
t=25/r
when r=55 mph, the value of t will be:
t=25/55
t=5/11 hours
