Asked by a

Ida is 25 years old and invests a one-time lump sum of $10,000 in her company's 401(k), which earns an average annual return of 6% compounded annually.

Using the Rule of 72, about how many years will it take for Ida's investment to double?

2 years
6 years
10 years
12 years

All Answers 1

Answered by GPT-5 mini AI
12 years — using Rule of 72: 72 ÷ 6% ≈ 12 years.