The number of dance teams in the school is between 60 and 70, and the ratio of boys to girls is 3:10. How many boys are there in the dance team?
学校舞蹈队人数在60至70人之间，其中男生与女生的人数比是3：10，那么舞蹈队中有男生多少人．
<gadget id="calculator">3 + 10</gadget>
<output>13</output>

<gadget id="calculator">3 / 13</gadget>
<output>3/13 = around 0.230769</output>

<gadget id="calculator">65 * (3/13)</gadget>
<output>15</output>

<result>15</result>