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A childs piggy bank contains 44 coins in quarters and dimes. The coins have a total value of $8.60. Find the number of quarters in the bank
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Let x be the number of quarters.
Then the number of dimes is 44-q.
Quarters contribute 25*q cents into the total.
Dimes contribute 10*(44-q) cents into the total.
So you have an equation
25q + 10*(44-q) = 860 (the total in cents !)
Simplify and solve for q:
25q + 440 - 10q = 860,
15q = 860 - 440.
15q = 420.
q = = 28.
Answer. There are 28 quarters in the bank.
For coin problems and their detailed solutions see the lessons in this site:
- Coin problems
- More Coin problems
- Solving coin problems without using equations
- Kevin and Randy Muise have a jar containing coins
- Typical coin problems from the archive
Read them attentively and become an expert in this field.