SOLUTION: Sam put $2,000 in a savings account at his bank. After 10 years, his account balance was $4,000. The interest rate on the savings deposit is __%. (Hint: Use the rule of 70 to sol

Algebra ->  Customizable Word Problem Solvers  -> Finance -> SOLUTION: Sam put $2,000 in a savings account at his bank. After 10 years, his account balance was $4,000. The interest rate on the savings deposit is __%. (Hint: Use the rule of 70 to sol      Log On

Ad: Over 600 Algebra Word Problems at edhelper.com


    

Question 1093676: Sam put $2,000 in a savings account at his bank. After 10 years, his account balance was $4,000. The interest rate on the savings deposit is
__%. (Hint: Use the rule of 70 to solve this problem.)
NextReset
Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
The rule of 70 is a way to estimate the number of years it takes for a certain variable to double. To estimate the number of years for a variable to double, take the number 70 and divide it by the growth rate of the variable.
10=70/int
int=70/10=7