Ryanne is 7 years older than Hezekiah. Together Ryanne's and Hezekiah's ages equal 15 years. How many years old is Hezekiah?
Let H = Hezekiah's age.
Ryanne = H + 
<gadget id="calculator">+7</gadget>
<output>7</output>
7
2H + 7 = 15
2H = 8.
H = 
<gadget id="calculator">4</gadget>
<output>4</output>
4.
Hezekiah is 4 years old.

<result>4</result>