Kelly Fisher invested a total of $20,000 in two municipal bonds that have yields of 8% and 9% interest per year, respectively.

Question

Formulate but do not solve the problem.

Kelly Fisher invested a total of $20,000 in two municipal bonds that have yields of 8% and 9% interest per year, respectively. If the interest Kelly receives from the bonds in a year is $1720, how much did she invest in each bond? (Let x and y denote the amount, in dollars, invested at 8% and 9%, respectively.)

		= 20,000
		= 1720

Answer 1

I will model it using 10000, 7%, 11%., and 1800 total interest

Obviously x + y = 10000 as she invests 10000 in total

Interest per year for first is 0.07 x (7% = 7/100 = 0.07)

Interest per year for second is 0.11y

TOTAL interest = 0.07x + 0.11y = 1800

You can use this model with your numbers

Mike