Quantitative Aptitude - Arithmetic Ability Questions

Which of the following pairs is NOT a pair of twin primes?

The mean of the data 3, 10, 10, 4, 7, 10, 5 is

ΔPQR is right angled at Q. If cosP = 3/5, then what is the value of cosR ?

In the following question, four groups of three numbers are given. In each group the second and third number are related to the first number by a Logic/Rule/Relation. Three are similar on basis of same Logic/Rule/Relation. Select the odd one out from the given alternatives.

From the top of a platform 5 m high, the angle of elevation of a tower was 30 deg. If the platform was positioned 40√3 m away from the tower, how tall was the tower?

If Cosecθ + Cotθ = 2, then Cotθ = ?

If 60/75 is equivalent to 4/x, then the value of x is

A cylindrical vessel of height 7 cm and radius 5 cm is completely filled with sand. When this sand is poured out it forms a right circular cone of radius 8 cm what will be the height of this cone?