



 
Hi Mary, You can do this by trial and error but I think you are expected to use algebra. There are two unknown numbers so give them names. I am going to call them $m$ and $n.$ The first requirement is that
Algebraically this says that \[m = n + 9.\] The second requirement is that
Write an algebraic expression for this requirement. In this expression replace $m$ using $m = n + 9.$ Solve for $n$ and then you know that $m = n + 9.$ Write back if you need more assistance,Penny  


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