Milimeters

The pool is 6 meters long and 3 meters wide, and the water in it is filled with water to a height of 1.7 m. When John jumped into it and completely submerged, the level had risen by 5.4 mm. How much weight does John when we know that one liter of the human body weighs approximately one kilogram?

Correct answer:

m =  97.2 kg

Step-by-step explanation:

$$\begin{gathered} a=6\text{m}\to \text{dm}=6\cdot 10\text{dm}=60\text{dm} \\ b=3\text{m}\to \text{dm}=3\cdot 10\text{dm}=30\text{dm} \\ c=1.7\text{m}\to \text{dm}=1.7\cdot 10\text{dm}=17\text{dm} \\ h=5.4\text{mm}\to \text{dm}=5.4:100\text{dm}=0.054\text{dm} \\ r=1\text{kg/l} \\ V=a\cdot b\cdot h=60\cdot 30\cdot 0.054=\frac{486}{5}=97.2\text{l} \\ 1l=1d{m}^3 \\ m=r\cdot V=1\cdot 97.2=97.2\text{kg} \end{gathered}$$

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