Quantitative Aptitude - Arithmetic Ability Questions

A and B together can complete a task in 12 days. However, if A works alone, completes half the job and leaves and then B works alone and competes the rest of the work, it takes 25 days in all to complete the work. If B is more efficient than A, how many days would it have taken B to do the work by herself?

If (x/y)a-4 = (y/x)2a-5, then what is the relation between x and y?

The standard deviation of the set {10, 11, 9, 11, 9} is

In the following question, four number pairs are given. The number on left side of (–) is related to the number of the right side of (–) with some Logic/Rule/Relation. Three are similar on basis of same Logic/Rule/Relation. Select the odd one out from the given alternatives.

A boy starts from his house and walks at a speed of 5 km/hr and reaches his school 3 minutes late. Next day he starts at the same time and increases hisspeed by 4 km/hr and reaches 3 minutes early. What is the distance (in km) between the school and his house?

For x > 0, what is the minimum value of  x + x+22x?

If sinC - sinD = x, then value of x is

In how many different ways can the letters of the word 'THERAPY' be arranged so that the vowels always come together?