Rajan is a fruit seller. On any day, he sells only one kind of fruit. On the first day, he buys 9 kg of blueberries. On the second day, he buys 22 kg of kiwis. On the third day, he buys 50 kg of peaches. The per kg purchase price of each fruit is an integer. Further, on each of these three days, he spends the same amount to purchase fruits. On the fourth day, he buys mangoes at Rs. 35/kg and spends Rs. 15 less than any of the previous three days.
If he then sells all the mangoes at Rs. 50/kg, what is his MINIMUM possible profit on the fourth day?

Let the price of blueberries, kiwis and peaches be Rs b, k and p respectively. 

Money spent on blueberries = Rs 9b

Money spent on kiwis = Rs 22k

Money spent on peaches = Rs 50p

Since, money spent everyday is the same, 

9b = 22k = 50p = M , where, M is the total money spent everyday. 

b = $$\ \frac{\ M}{9}$$

k = $$\ \frac{\ M}{22}$$

p = $$\ \frac{\ M}{50}$$

Since, b, k and p are integers, M should be the LCM of (9,22,50).

M = LCM (9,22,50) = LCM (22,450) = Rs 4950

Total money spent on the 4th day = Rs 4950 - Rs 15 = Rs 4935

Weight of mangoes bought on the 4th day = $$\ \frac{\ Rs\ 4935}{Rs\ \frac{35}{kg}}$$ = 141 kg

Cost Price of mangoes = Rs 35/kg

Sell Price of mangoes = Rs 50/kg

Profit on 4th day = $$\ \frac{\ Rs\ \left(50-35\right)}{kg}$$ $$\times\ $$141 kg = Rs 2115

Hence, the minimum possible profit on the 4th day is Rs 2115. 

$$\therefore\ $$ The required answer is B.