The weight of blood in the human body accounts for about 1/13 of the weight of the human body. Xiao Ming's weight is 39 kg. Find out how much the blood in his body weighs in kilograms.
人体血液重量约占人体重量的(1/13)，小明的体重是39千克，求他体内的血液重多少千克．
<gadget id="calculator">1 / 13</gadget>
<output>1/13 = around 0.076923</output>

<gadget id="calculator">39 * (1/13)</gadget>
<output>3</output>

<result>3</result>