# Exponential growth word problem

A coin sold for ?$\$ 269$in 1980 and was sold again in 1989 for$\$477$. Assume that the growth in the value $V$ of the? collector's item was exponential. ?

a) Find the value k of the exponential growth rate. Assume $V_0$ equals=269.
b) Find the exponential growth function in terms of? t, where t is the number of years since 1980. ?
c) Estimate the value of the coin in 2013. ?
d) What is the doubling time for the value of the coin to the nearest tenth of a? year?