Quantitative Aptitude - Arithmetic Ability Questions

A boat cover row 12 km upstream in 4 hours and can cover the same distance downstream in 3 hours. What is the speed (in km/hr) of the boat in still water?

What is the area (in square units) of the figure enclosed by the x-axis, the y-axis and the line x + 2y = 6 ?

The standard deviation of the set {10, 11, 12, 9, 8} is

In the following question, select the odd word pair from the given alternatives.

If x = 5 + 15 - 1 & y = 5 - 15 + 1, then find the value of x2 - y2.

A, B and C can do a job working alone in 12, 16 and 24 days respectively. In how many days they can do the job if they worked together?

The difference between Peter and Preeti's ages is 5 years. When they married each other 35 years ago, 4 times Peter's age was the same as 5 times the age of Preeti. What is the current sum of their ages?

The number of students in a class is increased by 20% and the number now becomes 66. Initially the number was