SOLUTION: Your piggy bank contains only dimes and quarters. If there are 73 coins in your piggy bank and the total of the coins is $14.50, how many dimes are ther in the bank?

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Question 507678: Your piggy bank contains only dimes and quarters. If there are 73 coins in your piggy bank and the total of the coins is $14.50, how many dimes are ther in the bank?
Answer by nic0le116(25) (Show Source):
You can put this solution on YOUR website!
What can we use for the value of of dimes? .10x
(since times are worth .10 and we don't know how many we have, so we multiply x amount of times.
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What can we use for the value of quarters? .25(73-x)
(since we know quarters are worth .25 and all we know about how many we have is that there is 73 minus however many dimes we have. since we used x for the amount of dimes, we subtract x)
Now we set it all equal to the total amount
.10x+.25(73-x)=14.50 (We add just like if we're trying to find the value of 10 times and 10 quarters. We would do .10*10+.25*10=___)
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Solve for x. Remember what did we decide x was? the amount of dimes.
.10x+.25(73-x)=14.50 (distribute .25 to the numbers inside of parenthesis)
.10x+18.25-.25x=14.50 (combine like terms on each side)
-.15x+18.25=14.50 (subtract 18.25 from each side)
-.15x=-3.75 (divide each side by -.15 to get x alone)
x=25
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There are 25 dimes.
If you're unsure subtract 25 from 73 to get the amount of quarters.
Multiply the values out and add them up to see if they equal 14.50
73-48=48 quarters
25*.10+.25*48= 14.50 CHECK!
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answer=25 dimes