Word Problem: Part of the topic is on Systems of Linear Equations: Two variables

Question

Question: Jolene invests her savings in two bank accounts, one paying 6 percent and the other paying 8 percent simple interest per year. She puts twice as much in the lower-yielding account because it is less risky. Her annual interest is 7760 dollars. How much did she invest at each rate?

 

I am looking for the answer on the Amount invested at 6 percent interest & Amount invested at 8 percent interest.

Answer 1

Let B = the amt at bigger interest and L = amt at lower interest

L = 28

.06L = amt of interest at lower rate and .08B = amt of interest at higher rate

.06L + .08B = total interest = 7760

Substitute

2B*.06 + .08B = .2B = 7760

Multiply by 5: B = 38800 and then L = 77600

Use these answers to make sure that the total amount of interest is correct.