SOLUTION: There are eight times as many 10 cent coins as there are 5 cent coins in a money box. The value of all the 10 cent coins is 450 cent more than the value of 5 cent coins. How ma

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: There are eight times as many 10 cent coins as there are 5 cent coins in a money box. The value of all the 10 cent coins is 450 cent more than the value of 5 cent coins. How ma      Log On


   

Question 740916:
There are eight times as many 10 cent coins as there are 5 cent coins in a money box. The value of all the 10 cent coins is 450 cent more than the value of 5 cent coins. How many 5 cent and 10 cent coins are there in the money box
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +n+ = number of 5 cent coins in box
Let +d+ = number of 10 cent coins in box
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(1) +d+=+8n+
(2) +10d+=+5n+%2B+450+ ( all values in cents )
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Substitute (1) into (2)
(2) +10%2A%28+8n+%29+=+5n+%2B+450+
(2) +80n+-+5n+=+450+
(2) +75n+=+450+
(2) +n+=+6+
and, since
(1) +d+=+8n+
(1) +d+=+8%2A6+
(1) +d+=+48+
There are 6 of the 5 cent coins in box
There are 48 of the 10 cent coins in box
check:
(2) +10d+=+5n+%2B+450+
(2) +10%2A48+=+5%2A6+%2B+450+
(2) +480+=+30+%2B+450+
(2) +480+=+480+
OK