The sum of the ages of a family of four is 75 years old, the father is 1 year older than the mother, and the elder sister is 2 years older than the younger brother. The sum of their ages 4 years ago was 60 years old, how old is my mother this year?
一家四口的年龄和是75岁，爸爸比妈妈大1岁，姐姐比弟弟大2岁．4年前他们的年龄和是60岁，问妈妈今年几岁？
<gadget id="calculator">4 * 4</gadget>
<output>16</output>

<gadget id="calculator">60 + 16</gadget>
<output>76</output>

<gadget id="calculator">76 - 75</gadget>
<output>1</output>

<gadget id="calculator">4 - 1</gadget>
<output>3</output>

<gadget id="calculator">2 + 3</gadget>
<output>5</output>

<gadget id="calculator">75 - 3 - 5 - 1</gadget>
<output>66</output>

<gadget id="calculator">66 / 2</gadget>
<output>33</output>

<result>33</result>