Quantitative Aptitude - Arithmetic Ability Questions

If w : 0.80 :: 9 : 6, w = ?

What is the area (in sq cm) of a regular hexagon of side 9 cm?

If Sin θ = 12/13, then what is the value of Cot θ?

If tan(A/2) = x, then the value of x is

In a bag the ratio of red balls to green balls is 4 : 9. If 6 more green balls were added to the bag, the ratio of red balls to green balls would become 1 : 3. How many red balls are there in the bag?

The orthocentre of an obtuse­angled triangle lies

The fraction from the ones listed below that will NOT lead to a recurring decimal is

The mean of 10 observations is 17. One more observation is included and the new mean becomes 16. The 11th observation is