Question

Toshiro has $850 to invest. He can invest in a savings account that has an annual interest rate of 3.7%, and he can invest in a money market account that pays about 5.5% per year. Write a polynomial to represent the amount of interest he will earn in 1 year if he invests x dollars in the savings account and the rest in the money market account.

a. 46.75-0.018x
b. 850 - 3.7x + 5.5y
c. 0.018x - 46.75
d. (3.7 + 5.5)x - 850

Answer 1

A = P (1 + r/n) (nt)
A = the future value of the investment
P = (the initial deposit or loan amount)
r = the annual interest rate (decimal)
n = the number of times that interest is compounded per year
t = the number of years the money is invested

Answer 2

a. 46.75 - 0.018x

Explanation:

He invest x dollars in the saving account and the rest in the money market account. It means that he invest x dollars in the saving account and (850-x) dollars in the money market account. Then, the amount of interest that he will earn in 1 year is:

I = 3.7%(x) + 5.5%(850-x)

Because, 3.7%(x) is the amount of interest earning by the saving account and 5.5%(850-x) is the amount of interest earning by the money market account. Therefore:

I = 3.7%(x) + 5.5%(850-x)

I = 0.037x + 0.055(850-x)

I = 0.037x + 46.75 - 0.055x

I = 46.75 - 0.018x