If are event occurs surely, then its probability is ___________

Two dice are through simultaneously the probability if getting a double is ___________

The standard deviation is the ____ of variance 

The mean of a observation x₁, x₂, x₃, ......... x_n is \(\bar { x } \). If each observation is multiplied by p, there the mean of the new observations is ___________

If the range and the smallest value of a set of data are 36.8 and 13.4 respectively, then find the largest value.

If the mean and coefficient of variation of a data are 15 and 48 respectively, then find the value of standard deviation.

Find the standard deviation of 30, 80, 60, 70, 20, 40, 50 using the direct method.

Find the standard deviation for the following data. 5, 10, 15, 20, 25. And also find the new S.D. if three is added to each value.

The marks scored by 5 students in a test for 50 marks are 20, 25, 30, 35, 40. Find the S.D for the marks. If the marks are converted for 100 marks, find the S.D. for newly obtained marks.

A bag contains 5 white and some black balls. If the probability of drawing a black ball from the bag is twice the probability of drawing a white ball then find the number of black balls.

Σx = 99, n = 9, Σ(x - 10)² = 79, then find,
(i) Σx²
(ii) Σ(x - \(\bar { x } \))²

Find the co-efficient of variation for the following data: 16, 13, 17,21, 18.

C.V. of a data is 69%, S.D. is 15.6, then find its mean.

S.D. of a data is 2102, mean is 36.6, then find its C.V.

Final the probability of choosing a spade or a heart card from a deck of cards.