Xiao Ming and Daming's family each have a group of ducks, and Xiao Ming's family raised 5 more ducks. The ratio of the number of ducks between the two is 3:4. Afterwards, Daming's family also raised 12 more ducks, and the ratio of the number of ducks between the two families became 5:8. So how many ducks did Daming's family have?
小明、大明家里各有一群鸭子，小明家多养了5只鸭子后．两家的鸭子数之比为3：4．之后大明家也多养了12只鸭子，两家的鸭子数之比变为5：8．那么大明家原来有鸭子多少只．
<gadget id="calculator">8 / 5</gadget>
<output>8/5 = around 1.6</output>

<gadget id="calculator">4 / 3</gadget>
<output>4/3 = around 1.333333</output>

<gadget id="calculator">(8/5) - (4/3)</gadget>
<output>4/15 = around 0.266667</output>

<gadget id="calculator">12 / (4/15)</gadget>
<output>45</output>

<gadget id="calculator">45 * (4/3)</gadget>
<output>60</output>

<result>60</result>