There are three boats A, B and C, working together they carry 60 people in each trip. One day an early morning A carried 50 people in few trips alone. When it stopped carrying the passengers B and C started carrying the people together. It took a total of 10 trips to carry 300 people by A, B and C. It is known that each day on an average 300 people cross the river using only one of the 3 boats A, B and C. How many trips it would take to A to carry 150 passengers alone?

Explanation:-

Combined efficiency of all the three boats = 60 passengers /trip
Now, consider option (1)
15 trips and 150 passengers means efficiency of A = 10 passengers per trip
A's efficiency = 10 passengers per trip
Then, (B + C) combined efficiency = 50 passengers per trip
Since, combined efficiency is 60 so option (1) is correct