Question 270272
.04x+.06*(x+3,000)=780
.04x+.06x+180=780
.10x=780-180
.10x=600
x=600/.10
x=6,000 ans. for the amount invested @ 4%.
6,000+3,000=9,000 ans. for the amount invested @ 6%.
Proof:
.04*6,000+.06*9,000=780
240+540=780
780=780