Xiaoqiang's weight is 42 kilograms, Fangfang's weight is 37 kilograms, how much is the difference in kilograms between the two.
小强的体重是42千克，芳芳的体重是37千克，两人相差多少千克．
<gadget id="calculator">42 - 37</gadget>
<output>5</output>

<result>5</result>