Quantitative Aptitude - Arithmetic Ability Questions

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

If sinA/(1 + cosA) = x, then x is

A basket contains 300 mangoes . 75 mangoes were distributed among some students . Find the percentage of mangoes left in the basket

Instead of multiplying by 25, a student multiplies that number by 52 and gets 324 more than correct answer. Then that number is

Karteek is twice as good a foreman as Raju and together they finish a piece of work in 20 days. In how many days will Raju alone finish the work?

The mean of 12 observations is 15. One more observation is included and the new mean becomes 16. The 13th observation is

The average age of 30 boys in a class is 10 years. If the age of their teacher is also included, the average increases by one year. The teacher's age in years is