There are 5 boxes of biscuits in a grocery store. If 30 kg are taken out of each box, the remaining biscuits in the 5 boxes are exactly equal to the weight of the original 3 boxes of biscuits. How many kilograms of biscuits are in each box?
某食品店有5箱饼干，如果从每个箱子里取出30千克，那么5个箱子里剩下的饼干正好等于原来3箱饼干的重量．原来每个箱子里装多少千克饼干．
<gadget id="calculator">5 / 2</gadget>
<output>5/2 = around 2.5</output>

<gadget id="calculator">30 * (5/2)</gadget>
<output>75</output>

<result>75</result>