Statistics and Probability Answers

1 The probability that Kodjo and Adoga pass an examination are 43and53 respectively. Find the probability of both boys failing the examination.
2 Three balls are drawn from a box containing 6 red marbles, 4 white marbles and 5 blue marbles. Find the probability that they are drawn in the order: red, white, and blue if each ball is drawn with replacement
3 When a die is thrown, what is the probability that the number is greater than 1, given that it is odd?
4 Giving that mean=34, median= 32 and standard deviation as 12. Calculate the Pearson's coefficient of skewness
5 Calculate the standard deviation of the marks: 2,3,6,2,5,0,4,2.
6 Find the mode of 3, 6, 10, 13, 14, 17, 19 and 22
7 Find the median of 3, 6, 10, 13, 14, 17, 19 and 22
8 calculate the arithmetic mean of 3, 6, 10, 13, 14, 17, 19 and 22
9 The data which has been collected for some other enquiry order than the one of immediate intereast is called ……..
10 From the set A= {3, p2; 2p3; p9; p7}, a number is selected at random. Find the proba

b) Vacuum cleaner sales for 12 months are given in the table below.
Month 1 2 3 4 5 6 7 8 9 10 11 12
Actual sales (in units) 10 12 13 16 19 23 26 30 28 18 16 14
i). Compute a simple 5-month average to forecast sales for month 13.

The masses of packages from a particular machine are normally distributed with a mean of 200g and a standard deviation of 2g. Find the probability that a randomly selected package from the machine weighs:
Less than 196g
Between 198.5g and 199.5g

Calculate the arithmetic mean of 3, 6, 10, 13,14,17,19 and 22
a) 20
b) 15
c) 13
d) 17

Find the mode of 3, 6, 10, 13,14,17,19 and 22
a) 20
b) 17
c) 20
d) 13

From the set A = {3, root 2, 2root 3, root 9, root7}, a number is selected at random. Find the probability that is a rational number.
a) 1/5
b) 2/5
c) 3
d) 4

Calculate the standard deviation of the marks: 2, 3,6,2,5,0,4,2
a) 1.5
b) 1.7
c) 1.8
d) 1.9

Giving that mean=34 median=32 and standard deviation as 12. Calculate the Pearson’s coefficient of skewness.
a) 0.1
b) 0.4
c) 0.5
d) 1.6

When a die is thrown, what is the probability that the number is greater than 1, given that it is odd?
a) 1/5
b) 3/5
c) 4/5
d) 2/5

Three balls are drawn from a box containing 6 red marbles, 4 white marbles and 5 blue marbles. Find the probability that they are drawn in the order: red, white, and blue if each ball is drawn with replacement
a) 8/225
b) 1/225
c) 4/225
d) 6/225