The floor

The floor collapsed because three and a half times the amount it had been designed to hold had been stored in the room. What amount was the floor designed to hold if we had stored 980 tons in the room?

Correct answer:

m =  280 t

Step-by-step explanation:

$$\begin{gathered} M=980\text{t} \\ k=3\frac{1}{2}=3+\frac{1}{2}=\frac{3\cdot 2+1}{2}=\frac{6+1}{2}=\frac{7}{2}=3.5 \\ m=M/k=980/\frac{7}{2}=980:\frac{7}{2}=980\cdot \frac{2}{7}=\frac{980\cdot 2}{7}=\frac{1960}{7}=280\text{t} \end{gathered}$$

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