A canteen requires 651 bananas for a week. Totally, how many bananas will it require for the months of April, May and June ?

Answer: Option A

Total number of days = (30 + 31 + 30) = 91
Let the number of bananas be x
More days, More bananas (Direct proportion)
$$\begin{array}{rl}& \therefore 7:91::651:x\\ & \Rightarrow 7x=91\times 651\\ & \Rightarrow x=\left(\frac{91\times 651}{7}\right)\\ & \Rightarrow x=8463\end{array}$$