A ball is thrown upward and its height is given by s(t) = -16t^2 + 96t, find the average velocity between t = 1s and t = 3s.

127

Step-by-step explanation:

s(t) = -16t^2 + 96t = -16t(t-6)

if t = 1 sec

-16t(t-6) = -16x1 (1-6) = -16(-5) = 90

if t= 3sec

-16x3(3-6) = -48(-3) = 144

the average velocity between 1 sec and 3 secs = (90+144)/2 = 254/2 = 127

b. 1.25 hr

step-by-step explanation:

if you have a constant speed of 60 mph, then you have a ratio between 60 mi. to 1 hr. dividing both sides by 60 we get the ratio

1 mi. to

then mult. both sides by 75 we get the ratio

75 mi. to

simplifying we get

75 mi. to

or 1.25 hr.