In a hostel, the number of students decreased by 5% and the price of food increased by 20% over the previous year. If each student consumes the same amount of food then By how much should the consumption of food be cut short by every student, so that the total cost of the food remains the same as that of the previous year?  Choose the correct choice:
A) 19%
B) 12.3%
C) 25%
D) 40%
E) 9.4%
Cost of food (C) = Food consumed per student (F) * Number of students (N) * Price of food (P)   Originally,   C = FNP   When number of students decrease by 5%, and the price of food increases by 20%,   C = F(new) * (0.95N) * (1.2P)   =&gt; F(new) = F/(0.95*1.2)   =&gt; F(new) = 0.877F   Therefore the new cost of food must be 87.7% of the old cost, or the cost of food must decrease by 12.28% (option12.3%)
<result>B</result>
In a hostel, the number of students decreased by 5% and the price of food increased by 20% over the previous year. If each student consumes the same amount of food then By how much should the consumption of food be cut short by every student, so that the total cost of the food remains the same as that of the previous year?