Question

The cost of 15 metres of a cloth is Rs 981. What length of this cloth can be purchased for Rs 1308?

Answer 1

Let the length of cloth be x m. Then, we have:
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Length of cloth (in metres)	15	x
Cost of cloth (in rupees)	981	1308

Clearly, more length of cloth can be bought by more amount of money.
So, this is a case of direct proportion.
$$\begin{gathered} \mathrm{Now},\frac{15}{981}=\frac{x}{1308} \\ \Rightarrow x=\frac{15\times 1308}{981} \\ \Rightarrow x=20 \end{gathered}$$

Therefore, 20 m of cloth can be bought for Rs 1,308.