Question 1128104
 Santiago receives ​$309 per year in simple interest from three investments. Part is invested at​ 2%, part at​ 3%, and part at​ 4%. There is​ $500 more invested at​ 3% than at​ 2%. The amount invested at​ 4% is six times the amount invested at​ 3%. Find the amount invested at each rate. Solve for the amount invested at each percent. 
Equations:
2t + 3r + 4f = 30900
r = t+500
f = 6*r
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Substitute and solve for "r"
2(r-500) + 3r + 24r = 30900
29r = 31900
r = $1100 (amt. invested at 3%)
f = 6r = $6600 (amt. invested at 4%)
t = r-500 = $500 (amt. invested at 2%)
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Cheers,
Stan H.
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