A collection of 70 coins consisting of dimes, quarters, and half-dollars has a value of 17.75. there are three timesas many quarters as dimes. Find the number of ecah kind of coin

Question

A collection of 70 coins consisting of dimes, quarters, and half-dollars has a value of 17.75. there are three timesas many quarters as dimes. Find the number of ecah kind of  coin

saifoo.khan · Answer

x+y+z=70;x=3y;4y+z=70
.25(3y)+.10y+.5z=17.75
.85y+.5z=17.75
85y+50z=1775
200y+50z=3500

 
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115y=1725
y=15
x=45
z=10
There are 45 quarters, 15 dimes, and 10 half-dollars in the coin collection..

anonymous · Answer

Thank you, but i still don't understand how you got the result. Would you please explain with a little bit of details. Thanks oce again :)