A ratio is 8:15, if the latter term of the ratio is increased by 60, how much should the former term of the ratio be increased to keep the ratio constant.
一个比是8：15，如果比的后项增加60，要使比值不变，比的前项应增加多少．
<gadget id="calculator">15 + 60</gadget>
<output>75</output>

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

<gadget id="calculator">8 * 5</gadget>
<output>40</output>

<gadget id="calculator">40 - 8</gadget>
<output>32</output>

<result>32</result>