The sum of the ages of A and B this year is 33 years old. After 4 years, A is 3 years older than B. Ask A how old this year is.
甲、乙两人今年的年龄和是33岁，4年后，甲比乙大3岁，问甲今年多少岁．
<gadget id="calculator">33 + 3</gadget>
<output>36</output>

<gadget id="calculator">36 / 2</gadget>
<output>18</output>

<result>18</result>