Big Ideas Math: Modeling Real Life, Grade 7
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Big Ideas Math: Modeling Real Life, Grade 7 View details
1. Probability
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Exercise 3 Page 288

Use the simple interest formula I=prt, where I is the interest, p the principal, r the annual interest rate, and t the time in years.

$ 36

Practice makes perfect
If we deposit money in a savings account, the bank pays us interest for the use of our money. To calculate the interest I, we use the simple interest formula. I= p r t, where... I& =Interest p& = Principal r& = Annual interest rate t& = Time (in years)We made a deposit of $480 in a savings account with an interest rate of 1.5 % = 0.015. We want to calculate the interest — how much we will earn in 5 years. p= 480, r= 0.015, t= 5 To calculate the interest, we will substitute these values into the simple interest formula and evaluate the right-hand side.
I=prt
I=( 480)( 0.015)( 5)
I=7.2(5)
I = 36
The earned interest is 36 dollars.