Answer:
"8.8%"
Step-by-step explanation:
Let x be the interest rate for the 20,000 and y for the 4,000
The problem says:
x20,000 = y4,000+1320 (1)
and
x = y+0.006 Substitute this value for x on equation (1)
(y+0.006)20,000 = y4,000+1320
20,000y+120 = y4,000+1320
16,000y = 1320
y = 0.0825 So the 4,000 are invested at 8.25%
And since x = y+0.006:
x = .0825+0.006 = 0.0885 or 8.8%. The 20,000 are invested at 8.8%
