Question 1005943
Call their costs, a and p. Then we have
2a + 5p = 320  (work in cents)
4a + 9p = 600
Let's double the first one and subtract it from the first...we get
4a + 9p = 600
-(4a + 10p = 640)
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-p = -40
p = 40 cents per plum
Substituting that into the first equation gives us
2a + 5(40) = 320
2a + 200 = 320
2a = 120
a = 60 cents per apple