<PRE><B>Question 1158877</B>
&lt;pre&gt;
There are two equations, but they can be collapsed into one (and solved!):
M = Z + 10  
M + Z = 23

(Z+10)+Z = 23   &lt;&lt;&lt; this equation represents the stated problem, with one unknown
2Z = 13         &lt;&lt;&lt; simplified
Z = 13/2 = 6 1/2   &lt;&lt;&lt; solved (it is very unusual for age problems to have fractional answers)

Since Zohar is 6 1/2, Maria must be 16 1/2.

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