Question

Word Problem: Arlene wishes to invest $5000. If she invests part at 7% simple interest, part at 6%, and receives a total of $332 after one year, how much does she invest at each rate?

Answer 1

seven@7% = (332 - 5000(.06))/(.07 -.06)

Answer 2

id say 3200 @ 7% and the rest at 6%

Answer 3

a + b = t; find an equation for all the money split into 2 parts

ax + by = z; determine an equation that accounts for the percents
and the total amount at the end

now eliminate one of the parts


a + b = t; *-x
ax + by = z




-ax -bx = -tx
ax+by = z
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b(y-x) = (z -tx)

b@y = (z-tx)/(y-x)