<PRE><B>Question 96988</B>
Lane invested $22,000, part at 8% and part at 7%.  If the total interest at the end of the year is $1,710, how much did she invest at 8%?

I=prt
1710 = .08x + .07(22000 - x)
Multiply both sides by 100 to remove the decimals
171,000 = 8x + 7x(22000 - x)
171,000 = 8x + 154,000 - 7x
171,000 = x + 154,000
17,000 = x

To check:
17,000 * 8% = 1360
(22,000 - 17,000) =  5,000 * 7% = 350
So 1360 + 350 =1710</PRE>