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

If sinA + sin2A =1 then what is the value of cos2A + cos4A

What is the simplest form of (1 + cosA)(cosecA ­ cotA)?

If 4x + 5y = 14 and x - 5y = 16 then the value of x and y are

The difference between the place values of 9 and 5 in the number 428693745 is

PQ is a diameter of a circle with centre O. RS is a chord parallel to PQ subtends an angle of 40° at the centre of the circle. If PR and QS are produced to meet at T, then what will be the measure (in degrees) of ∠PTQ?

In a triangle the length of the side opposite the angle which measures 45° is 8 cm, what is the length of the side opposite to the angle which measures 90°?

O is the centre of the circle and ∠AOB = 150°, and the shaded portion is x part of the circular region, then x = ?