The weight of blood in the human body is about (1/13) of the body weight, and the blood contains about (13/25) of water. Uncle Zhang weighs 75 kilograms, how many kilograms of water is in his blood?
人体内血液的重量大约是体重的(1/13)，血液内大约含(13/25)的水．张叔叔的体重是75千克，他的血液内大约含水多少千克？
<gadget id="calculator">1 / 13</gadget>
<output>1/13 = around 0.076923</output>

<gadget id="calculator">13 / 25</gadget>
<output>13/25 = around 0.52</output>

<gadget id="calculator">75 * (1/13) * (13/25)</gadget>
<output>3</output>

<result>3</result>