Question 206
You should ask two questions separately, but here goes. <BR>

Denote the amount invested at 7% as x dollars. The remaining amount to be invested is, obviously, 2000-x. Amount of interest at 7% is x*0.07. Amount of interest invested at 8% is (2000-x)*0.08. So, we have x*0.07+(2000-x)*0.08 = 154. <BR>

x*0.07+2000*0.08 - x*0.08 = 154<BR>
2000*0.08-154 + x*0.07 - x*0.08 = 0<BR>
160-154-0.01x = 0<BR>
6 = 0.01x<BR>
x = 600, 2000-x = 1400<BR>
Answer: He invested $600 at 7% and $1,400 at 8%.<BR>

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