+1 Ralph invests $15,600 into two different acconunts; a savings account and checking account. The savings account earns 8% interest. The checking account earns 9% interest. After 1 year he earned $1334.28 interest. How much did Ralph invest into each account?
+33654 savings + checking = 15600
0.08*savings + 0.09*checking = 1334.28
Use the first in the second:
0.08*(15600 - checking) + 0.09*checking = 1334.28
0.01*checking + 0.08*15600 = 1334.28
0.01*checking = 1334.28 - 1248
0.01*checking = 86.28
checking = 86.28/0.01 = $8628
savings = 15600 - 8628 = $6972
.
+33654 savings + checking = 15600
0.08*savings + 0.09*checking = 1334.28
Use the first in the second:
0.08*(15600 - checking) + 0.09*checking = 1334.28
0.01*checking + 0.08*15600 = 1334.28
0.01*checking = 1334.28 - 1248
0.01*checking = 86.28
checking = 86.28/0.01 = $8628
savings = 15600 - 8628 = $6972
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