Quantitative Aptitude - Arithmetic Ability Questions

The arithmetic mean of the marks scored by students of a class is 58. 20% of them secured a mean score of 60. The mean score of another 30% of the students was 40. The mean score of the remaining students is

Rs 9000 is divided among P, Q and R in the ratio of 5 : 6 : 7. What is the share (in Rs) of R?

What is the area (in sq cm) of a rectangle of perimeter 48 cm and breadth 10 cm?

What must be the length (in cm) of the diagonal of a rectangle if its area and breadth are 60 cm² and 5 cm respectively?

What is the value of ( 1/2 - cot45) ?

Deepinder lent Rs 8200 to Jairaj for 16 years and Rs 4900 to Karna for 15 years on simple interest at the same rate of interest and received Rs 19446.5 in all from both of them as interest. The rate of interest per annum is:

The surface area of a sphere is 1386 cm2.  Find its diameter (in cm)

From a point on a bridge across the river, the angles of depression of the banks on opposite sides of the river are 30° and 45° respectively. If the bridge is at a height of 2.5m from the banks, then the width of the river is (take √3 = 1.732)