Quantitative Aptitude - Arithmetic Ability Questions

The mode of the data 12, 1, 10, 1, 9, 3, 4, 9, 7, 9 is

Among four students sitting in a row, average age of last three students is 20 years and the average age of first three students is 21 years. If the age of first student is 26 years, then what is the age (in years) of the last student?

Koushik can do a piece of work in X days and Krishnu can do the same work in Y days. If they work together, then they can do the work in

Pipe A can empty a filled tank in 28 hours while Pipe B can fill the same tank, when empty in 35 hrs. If alternatively Pipes A and B are turned on for an hour each time, starting when the tank is full, how long will it take to empty the tank?

Select the odd word/letters/number/number pair from the given alternatives.

Which one of the following is true for 0°<θ<90°

For which value of ‘g’ the linear graph of 6x + 12y +9 = 0 and 2x + gy + 3 = 0 has infinite number of solutions?