Question 1050005
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Dan opened up his piggy bank and found a total of 35 coins - nickels, dimes, quarters.  
He has 5 more nickels than dimes and a total of $6.  How many of each coin were in his bank?
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<pre>
Let "d" be the number of dimes.
Then the number of nickels is d+5, according to the condition.
Then the number of quarters is (35 - d - (d+5)) = 35 - 2d -5 = 30 - 2d.

Nickels contribute 5*(d+5) cents to the total.
Dimes contribute 10d cents to the total.
Quarters contribute 25*(30-2d) cents to the total.

An equation for the total is

5*(d+5) + 10d + 25*(30-2d) = 600 cents.

Simplify it:

5d + 25 + 10d + 750 - 50d = 600,

5d + 10d - 50d = 600 - 25 - 750,

-35d = -175  --->  d = {{{(-175)/(-35)}}} = 5.

There were 5 dimes.

Now you find all remaining unknowns.
</pre>

There is entire bunch of the lessons on coin problems

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=http://www.algebra.com/algebra/homework/word/coins/Coin-problems.lesson>Coin problems</A>

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=http://www.algebra.com/algebra/homework/word/coins/More-Coin-problems.lesson>More Coin problems</A>

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=http://www.algebra.com/algebra/homework/word/coins/Solving-coin-problem-without-equations.lesson>Solving coin problems without using equations</A>

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=https://www.algebra.com/algebra/homework/word/coins/Kevin-and-Randy-Muise-have-a-jar.lesson>Kevin and Randy Muise have a jar containing coins</A>

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=https://www.algebra.com/algebra/homework/word/coins/Typical-coin-problems-from-the-archive.lesson>Typical coin problems from the archive</A>

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=https://www.algebra.com/algebra/homework/word/coins/More-complicated-coin-problems.lesson>More complicated coin problems</A>

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=http://www.algebra.com/algebra/homework/word/coins/OVERVIEW-of-lesson-on-coin-word-problems.lesson>OVERVIEW of lessons on coin word problems</A>

in this site.


Read them and become an expert in solution of coin problems.


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