The age of the mother is four times that of the son. What is the age of the mother when the child is born at the age of 27?
母亲现在的年龄是儿子的4倍，母亲27岁生下的这个孩子，现在母亲的年龄是多少岁．
<gadget id="calculator">27 / 3</gadget>
<output>9</output>

<gadget id="calculator">9 * 4</gadget>
<output>36</output>

<result>36</result>