The blood mass of a person accounts for about (1/13) of body weight, and the mass of water in blood accounts for (2/3). According to this calculation, how many kilograms of water is contained in your blood?
一个人的血液质量约占体重的(1/13)，血液中水分的质量占了(2/3)．照这样计算，你的血液里约含水分多少千克？
<gadget id="calculator">1 / 13</gadget>
<output>1/13 = around 0.076923</output>

<gadget id="calculator">2 / 3</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">39 * (1/13) * (2/3)</gadget>
<output>2</output>

<result>2</result>