Answer:
23.1 years (nearest tenth)
Explanation:
Compound Interest Formula

where:
- A = final amount
- P = principal amount
- r = interest rate (in decimal form)
- n = number of times interest applied per time period
- t = number of time periods elapsed
Given:
- A = $1200
- P = $600
- r = 3% = 0.03
- n = 12 (as compounded monthly)
- t = years
Substitute the given values into the formula and solve for t:




Take natural logs:





The money will double in value in approximately
years.