Problema Solution
Mike invested $526 for one year. He invested part of it at 2% and the rest at 5%. At the end of the year he earned $20.57 in interest. How much did Mike invest at each rate of interest?
Answer provided by our tutors
0.02 · 526 + 0.05 · 526 = 20.57
x + y = 526; 2x + 5y = 20.57
x + y = 526; 0.02x + 0.05y = 20.57
0.02x + 0.05y = 526; x + y = 20.57
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x + y = 526; 0.02x + 0.05y = 20.57 is the equation