Need help with an easy maths question, I know how to find the answer but I'm pritty sure there is a faster way of doing it . What is the fastest way of doing this? Is there a formula for this, i forgot how to do it the fast way:/

Initial height: 1.2m
Rate of growth = 9% (1.09 as a decimal)

Answer: 1.2 * 1.09^6 (6 years)
= 2.01m (2decimal places)
= 201cm