The number of students in Class 1 is between 50 and 60, and the ratio of male to female is 5:4, so how many boys are there?
六1班人数在50到60之间，男女人数比是5：4，那么男生有多少人．
<gadget id="calculator">5 + 4</gadget>
<output>9</output>

<gadget id="calculator">5 / 9</gadget>
<output>5/9 = around 0.555556</output>

<gadget id="calculator">54 * (5/9)</gadget>
<output>30</output>

<result>30</result>