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Question
If the cost of 93 m of a certain kind of plastic sheet is Rs 1395, then what would it cost to buy 105 m of such plastic sheet?
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Solution
| Length of plastic sheet (in metre) | 93 | 105 |
| Cost (in Rs) | 1395 | x |
Let the cost of the plastic sheet per metre be Rs x.
If more sheets are bought, the cost will also be more
Therefore, it is a direct variation.
We get:
93 : 105 = 1395 : x
\[ \Rightarrow \frac{93}{105} = \frac{1395}{x}\]
Applying cross muliplication, we get:
x = `(105xx1395)/93`
x = 1575
Thus, the required cost will be Rs 1,575.
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