A postal clerk sold 75 stamps for $4.80. Some were 5-cent stamps and others were 8-cent stamps. How many of each type of stamp did he sell?

Question

goformit100 · Answer

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anonymous · Answer

let x = 5 cent stamps and y = 8 cent stamps,
youll get these equations:

x + y = 75 which is the number of stamps
5x + 8y = 480 which is the value of the stamps.

anonymous · Answer

if you still cant solve them, 
x = 75 - y, sub in 2nd eq,

5(75-y) + 8y = 480
375 + 3y = 480
3y = 105
y= 35

then sub back into 1st eq,
x + 35 = 75
x = 40