Phyllis invested 11,500 a portion earning a simple interest rate of, 6.25% per year and the rest earning a rate of 6% per y

Question

Phyllis invested 11,500 a portion earning a simple interest rate of, 6.25% per year and the rest earning a rate of 6% per year. After one year the total interest earned on these investments was $711.25. How much money did she invest at each rate?

At 6.25% per year?

At 6% per year?

Answer 1

X+y = 11500

0.0625x + 0.06y = 711.25

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0.0625 x + 0.06 (11500-x) = 711.25

0.0625x + 690 - 0.06x = 711.25

0.0025x = 21.25

x = 8500

y = 3000