Question

Suppose the population in a town has an average growth rate of 18%. If there are 15,500 people now living in town in about how many years will the population grow to 30,000? Use the equation 30,000=(15,500)(1.18)^x and round the value of x to the nearest year

Answer 1

This is an equation with the variable as an exponent.
Have you come across this type before?

Answer 2

first isolate the exponential bit by dividing both sides by 15,500

(1.18)^x = 30,000/15,500

Answer 3

now you take logarithms of both sides
ln (1.18)^x = ln (30,000/15500)

can you continue from here?

Hint;- use the rule ln a^b = b ln a