SOLUTION: A stationery company sells two types of notepads to college bookstores, the first wholesaling for 50¢ and the second for 70¢. The company receives an order for 550 notepads, togeth

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Question 597990: A stationery company sells two types of notepads to college bookstores, the first wholesaling for 50¢ and the second for 70¢. The company receives an order for 550 notepads, together with a check for $311. If the order fails to specify the number of each type, how should the company fill the order?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +a+ = number of 50 cent notepads ordered
Let +b+ = number of 70 cent notepads ordered
--------
given:
(1) +a+%2B+b+=+550+
(2) +.5a+%2B+.7b+=+311+
-----------------
(2) +5a+%2B+7b+=+3110+
Multiply both sides of (1) by 5
and subtract (1) from (2)
(2) +5a+%2B+7b+=+3110+
(1) +-5a+-+5b+=+-2750+
+2b+=+360+
+b+=+180+
and, since
(1) +a+%2B+b+=+550+
(1) +a+%2B+180+=+550+
(1) +a+=+370+
370 50 cent notepads were ordered
180 70 cent notepads were ordered
check:
(2) +.5a+%2B+.7b+=+311+
(2) +.5%2A370+%2B+.7%2A180+=+311+
(2) +185+%2B+126+=+311+
{2) +311+=+311+
OK