It is known that the number of students in school A is 40% of the number of students in school B, the number of girls in school A is 30% of the number of students in school A, and the number of boys in school B is 42% of the number of students in school B, so the total number of boys in the two schools accounts for two What percentage of the total number of students?
已知甲校学生人数是乙校学生人数的40%，甲校的女生人数是甲校学生数的30%，乙校男生人数是乙校学生数的42%，那么两校男生总数占两校学生总数的百分之几？
<gadget id="calculator">42 / 100</gadget>
<output>21/50 = around 0.42</output>

<gadget id="calculator">40 / 100</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">30 / 100</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">1 - (3/10)</gadget>
<output>7/10 = around 0.7</output>

<gadget id="calculator">(2/5) * (7/10)</gadget>
<output>7/25 = around 0.28</output>

<gadget id="calculator">(21/50) + (7/25)</gadget>
<output>7/10 = around 0.7</output>

<gadget id="calculator">1 + (2/5)</gadget>
<output>7/5 = around 1.4</output>

<gadget id="calculator">(7/10) / (7/5)</gadget>
<output>1/2 = around 0.5</output>

<result>1/2 = around 0.5</result>