Quantitative Aptitude - Arithmetic Ability Questions

Find the sum of interior angles of a decagon?

ΔDEF is right angled at E. If cosecD = 5/4, then what is the value of cosecF?

An aeroplane flying horizontally at a height of 3 Km. above the ground is observed at a certain point on earth to subtend an angle of 60°. After 15 sec flight, its angle of elevation is changed to 30°. The speed of the aeroplane (taking √3 = 1.732) is

A circle is inscribed in a square. If the length of the diagonal of the square is 14√2 cm, what is the area of the circle?

Which of the following is correct?

What is the value of ( 1/3 - cosec30°) ?

In a triangle the length of the side opposite the angle which measures 60° is 6√3 cm. What is the length of the side opposite to the angle which measures 90°? 

The triangle ABC and DEF are similar to each other. The measure of the angle A and E is 67 and 83 degree respectively. What is the value of angle C?