The average weight of students in Classes 4 and 5 is 40 kg. Xiao Liang’s weight is 55 kg and recorded as +15 kg. Xiao Hong’s weight of 35 kg should be recorded as how many kg.
四、五班同学的平均体重为40千克，小亮的体重为55千克记做+15千克，那小红的体重35千克应记做多少千克．
<gadget id="calculator">40 - 35</gadget>
<output>5</output>

<result>5</result>