Quantitative Aptitude - Arithmetic Ability Questions

Pipes A and B, when working together, can fill an empty tank in 8 hours. If B is stopped after 2 hours, it will take a total of 11 hrs to fill the tank. How long would it take A to fill the empty tank alone?

If PA and PB are two tangents to a circle with centre O such that ∡APB = 80°. Then ∡AOP = 

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

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

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

30% of a number exceeds 25% of the same number by 27. What is the value of the number?

If a.sin 45°.cos 45°.tan60° = tan 245° ­ cos60° then find the value of a ?

If (tanA + tanB)/(1 ­ tanAtanB) = x, then the value of x is