Question

Sales of televisions grow at a rate proportional to the amount present (t is measured in days)

(a) Set up a differental equation to model this problem
(b) Solve the differential equation if at t=0, there are 20 televiosions sold and after 3 days, 500 televisions are sold.
Reiny
sales = a(e^(kt))

if t=0, sales = 20
20 = a(e^0_
a = 20

then sales = 20(e^(kt)
when t=3, sales = 500

500 = 20(e^3k))
e^(3k) = 25
3k = ln 25
k = 1.07296

sales = 20(e^(1.07296t)