Hope Primary School has 450 students, the number of girls is 4/5 of the number of boys, how many boys are there in Junwu Primary School?
希望小学有学生450人，女生人数是男生人数的(4/5)，君武小学男生有多少人？
<gadget id="calculator">4 / 5</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">1 + (4/5)</gadget>
<output>9/5 = around 1.8</output>

<gadget id="calculator">450 / (9/5)</gadget>
<output>250</output>

<result>250</result>