<PRE><B>Question 250715</B>
The equation for company 1 is
C = 4S, where C = total cost and S = cost per shirt.
The equation for company 2 is
C = 3S + 75.
The cost is the same when both equations are equal to each other. So,
4S = 3S + 75
S = 75; the answer
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The check:
If S = 75, the cost for company 1 is 
C = 4*75 = $300
If S = 75, the cost for company 2 is
C = 3*75 + 75 = 225 + 75 = $300.</PRE>