Question 973272
Joshua pays $9.10 for a bag and has $16.25 left. 
<pre>
{{{(matrix(7,1,

The,amount,of,money,Joshua,starts,with))}}}{{{""=""}}}{{{(matrix(9,1,

The,amount,of,money,he,spends,for,the,bag))}}}{{{""+""}}}{{{(matrix(7,1,

The,amount,of,money,he,has,left))}}}{{{""=""}}}{{{"$9.10"+"$16.25"}}}{{{""=""}}}{{{"$25.35"}}}
</pre>
Sally and Joshua have the same amount of money.
<pre>
Therefore Sally also starts with $25.35.
</pre>
Sally buys a pen and has $19.60 left. How much does the pen cost? 
<pre>
{{{(matrix(7,1,The,amount,of,money,the,pen,costs))}}}{{{""=""}}}{{{(matrix(7,1,

The,amount,of,money,Sally,starts,with))}}}{{{""-""}}}{{{(matrix(7,1,

The,amount,of,money,she,has,left))}}}{{{""=""}}}{{{"$25.35"-"$19.60"}}}{{{""=""}}}{{{"$5.70"}}}

Edwin</pre>