A sum of $2100 is invested in two accounts, one earning 7% simple annual interest and one earning 4%. If the total interest earned for the year is $120, how much money is in each account?

Question

anonymous · Answer

if you could just help me set the equation up that would be very helpfull

gw2011 · Answer

Let x = 7% investment
Let y = 4% investment

0.07x+0.04y=120
x+y=2100   Multiply this equation by 0.04 to find x and you get:

0.07x+0.04Y=120
0.04x+0.04y=84   Subtract this equation from the first one and you get:

0.03x=36
x=1200

Y=2100-1200=900

Therefore, the 7% investment is $1200 and the 4% investment is $900