Question:
The cost of 15 metres of a cloth is Rs 981. What length of this cloth can be purchased for Rs 1308?
Solution:
Let the length of cloth be x m. Then, we have:
| 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.
Now, $\frac{15}{981}=\frac{x}{1308}$
$\Rightarrow x=\frac{15 \times 1308}{981}$
$\Rightarrow x=20$
Therefore, 20 m of cloth can be bought for Rs 1,308.