The sum of the ages of the father, mother and daughter is 72 years old, the age of the father is 7 times that of the daughter, the mother is 3 years younger than the father, how old is the mother.
爸爸、妈妈和女儿三个人的年龄之和是72岁，爸爸的年龄是女儿的7倍，妈妈比爸爸小3岁，妈妈多少岁．
<gadget id="calculator">3 + 72</gadget>
<output>75</output>

<gadget id="calculator">7 + 7 + 1</gadget>
<output>15</output>

<gadget id="calculator">75 / 15</gadget>
<output>5</output>

<gadget id="calculator">7 * 5</gadget>
<output>35</output>

<gadget id="calculator">35 - 3</gadget>
<output>32</output>

<result>32</result>