Question

5 men catch 5 crabs in 5 hours. How many men are required to catch 1000 crabs in 1 hour?

Answer 1

$$\begin{gathered} \mathrm{Using}\mathrm{the}\mathrm{concept}, \\ \frac{\mathrm{man}\times \mathrm{day}}{\mathrm{work}}=\mathrm{constant} \\ \frac{{\mathrm{m}}_1\times {\mathrm{d}}_1}{{\mathrm{w}}_1}=\frac{{\mathrm{m}}_2\times {\mathrm{d}}_2}{{\mathrm{w}}_2} \\ \Rightarrow \frac{5\times 5}{5}=\frac{{\mathrm{m}}_2\times 1}{1000} \\ {\mathrm{m}}_2=5000 \end{gathered}$$