Rule Of 72 Math Worksheet Dave Ramsey Answer Key
1. Doug invested $2,500 into a Certificate of Deposit earning 6.5% interest. How long will it take to double Doug’s investment?
Answer: 72/6.5 = 11 years.
The correct answer is 11 years.
2. The average Stock Market return since 1926 has been 11%. According to the Rule of 72, how often will an individual’s investment double in that time?
Answer: 72/11 = 6.5 years.
The correct answer is 6.5 years.
3. Jessica has a balance of $2,200 on her credit card with an 18% interest rate. Her credit card company doesn’t require a minimum payment on the balance (unheard of) and does not assess any late charges (also unheard of). If Jessica chooses not to make any payments on her outstanding balance, how long will it take for her balance to double?
Answer: 72/18 = 4 years.
The correct answer is 4 years.
4. Jacob has $5,000 that he has saved from doing odd jobs around the neighborhood. When he graduates from college in four years, he would like to have $10,000 to use as a down payment on a new car. If Jacob is going to realize his dream, what interest rate will he have to invest his money at?
Answer: 72/4 = 18% years.
The correct answer is 18% years.
5. Rhonda is 22 years old and would like to invest $2,000 into a U.S. Treasury Note earning 7.5% interest. How many times will Rhonda’s investment double before she draws it out at age 70?
Answer: 72/7.5 = 9.6 (Money will double in 9.6 years)
70 – 22 = 48 years 48 / 9.6 = 5 times (her money will double 5 times until she is 70.
The correct answer is 70