SOLUTION: An office manager ordered 60 stamps for a total of $21.70. There were only 42-cent and 17-cent stamps in order?

Question 749042: An office manager ordered 60 stamps for a total of $21.70. There were only 42-cent and 17-cent stamps in order?
Answer by Cromlix(4381) (Show Source): You can put this solution on YOUR website!
x = 42 cent stamp
y = 17 cent stamp
x + y = 60....1
42x + 17y = 2170..2

Multiply (1) by 42

42x + 42y = 2520...1
42x + 17y = 2170...2
Subtract (2) from (1)
25y = 350
y = 350/25 = 14
Substitute y = 14 into
x + y = 60
x + 14 = 60
x = 60 - 14
x = 46
Therefore there are:
46 x 42 cent stamps and
14 x 17 cent stamps
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