61.54%
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To find the percentage increase, we need to compare the initial price per litre to the final price per litre. The initial price is 65 naira per litre and the final price is 105 naira per litre.
The difference between the two prices is:
- 105 - 65 = 40 naira per litre
To find the percentage increase, we need to divide the difference by the initial price and multiply by 100.
So, the percentage increase is:
Therefore, the percentage increase is 61.54%.