Dig water well

Mr. Zeman is digging a well. Its diameter is 120 cm, and it is planned to be 3.5 metres deep. How long (at minimum) must a ladder be for Mr. Zeman to climb out?

Final Answer:

x =  3.7 m

Step-by-step explanation:

$$\begin{gathered} d=120\text{cm}\to \text{m}=120:100\text{m}=1.2\text{m} \\ h=3.5\text{m} \\ x=\sqrt{h^2+d^2}=\sqrt{3.5^2+1.2^2}=3.7\text{m} \end{gathered}$$

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