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Question

Juan invested a total of $2900, part at 10% simple interest and part at 13% simple interest. At the end of 1 year, the investments had earned $338. How much was invested at each rate?

Answer 1

.10x + (2900-x).13 = 338

-.03 x= 338-377=-39

x = 39/.03 = $1300 invested at 10%

and 2900-1300 = $1600 invested at 13%

.1(1300) + .13(1600) = 130 + 208 = 338