# MATH 105 PLEASE HELP!?

Maria’s parents tell them that they will set up a savings account for their first grandchild. They have $10,000 to invest and have identified an account that pays 3% compounded weekly. Since Maria and John both just finished a course on consumer mathematics, they each decide to calculate how much interest will have been earned at the end of 10 years and the end of 18 years.

Maria is very precise and never rounds her decimal places until the end of her calculations.

John always rounds each intermediate step to 5 decimal places.

Answer each of the following questions separately, showing all your work to reach each answer.

a. How much interest will Maria calculate for each time period (10 years and 18 years)?

b. How much interest will John calculate for each time period? (10 years and 18 years)?

### 2 Answers

- MichaelLv 71 month ago
Maria

10 years

10000(1 + .03/52)^(10*52)

13,497.42

interest = $3,497.42 <–––––––

18 years

10000(1 + .03/52)^(18*52)

17,157.40

interest = $7,157.40 <–––––––

----------------------------------

John

.03/52 = 0.000576923076923

To 5dp

0.00058

10 years

10000(1 + 0.00058)^(10*52)

13,519.02

interest = $3,519.02 <–––––––

18 years

10000(1 + 0.00058)^(18*52)

17,206.85

interest = $7,206.85 <–––––––