Question 1054057
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conor collects 10 cent 20 cent and 50 cent coins. he saves 13.50. he saved twice as many 10 cent coins as 50 cent coins 
and 4 times as many 20 cent coins as 50 cent coins. how many 50 cent coins did he save?
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<pre>
Let x be the # of 50-cent coins.
Then the number of 10-cent coins is 2x, 
and  the number of 20-cent coins is 4x. 

then 50-cent coins contribute 50x cents to the total;
     10-cent coins contribute 10(2x) cents to the total;
     20-cent coins contribute 20(4x) cents to the total.

The "value equation" is

     50x + 10(2x) + 20(4x) = 1350 cents,  or

     50x + 20x + 80x = 1350,   or

     150x = 1350  --->  x = {{{1350/150}}} = 9. 

<U>Answer</U>.  The number of 50-cent coins was 9.
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