In the given figure, PQ is a chord of a circle with center O and PT is the tangent at point P. If angle QPT = 60°, then find angle PRQ where R is a point on the circle.

The following table shows a record of the weights, in kilogram, of 100 pupil. Find the mean weight.

For what value of n, the nth term of A.P. 63, 65, 67, ….. and nth term of A.P. 3, 10, 17, …… are equal ?

Three coins are tossed once. Find the probability of getting :

(i) 3 heads

(ii) exactly two heads

(iii) atleast 2 heads.