Answer & Explanation
B) Rs. 30
From the given data,
When the price of rice is decreased by 10%, the value of Rs. 270 would become
270 x 100/90 = 300
Now, the value 270 becomes 300
And given, the girl could buy 1 kg extra for that value
Change in value = 300 - 270 = Rs. 30
Therefore, 1 kg extra rice she can get for Rs. 30
=> The original price of rice = Rs. 30/kg.
As she gets only 9 kgs for Rs. 270 before 10% discount, now after discount she gets 10 kgs instead of 9 kgs for Rs. 270.