QUIZ
MATHEMATICS AND ACTUARIAL SCIENCE
PROBABILITY AND STATISTICS
1. Suppose that in a game, a single dice is tossed in order to determine
how much money a player expects to win. The dice is fair and one
wins Kshs. 30,000 if a two turns up. A total of Kshs.50,000 is won if a
three turn up and a player looses Kshs. 20,000 if a five turns up. For
all other number that appear on top nothing is won.
Find the expected money to be won. (5 Marks)
2. The average number of calls that are recorded y a receptionist in a day
is 6. Find the probability that the receptionist receives 10 calls in a
particular day. (5 Marks)
3. What is the probability of getting 3 heads in a 5 tosses of a fair coin?
(5 Marks)
4. Construct a straight line from the given points below:
X 1.2 1.8 3.1 4.9 5.7 7.1 8.6 9.8
Y 4.5 5.9 7.0 7.8 7.2 6.8 4.5 2.7
Find the equation of the line of regression of Y on X using the points
given above (10 Marks)
5. The table below shows the weights to the nearest pound of boys and
girls in a certain school:
BOYS 64 53 67 55 58 77 57 56 51 76 68
GIRLS 57 49 62 51 50 55 48 52 42 61 57
Calculate Karl Pearson’s correlation coefficient of those boys and girls
in that school (15 Marks)
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MATHEMATICS AND ACTUARIAL SCIENCE
PROBABILITY AND STATISTICS
1. Suppose that in a game, a single dice is tossed in order to determine
how much money a player expects to win. The dice is fair and one
wins Kshs. 30,000 if a two turns up. A total of Kshs.50,000 is won if a
three turn up and a player looses Kshs. 20,000 if a five turns up. For
all other number that appear on top nothing is won.
Find the expected money to be won. (5 Marks)
2. The average number of calls that are recorded y a receptionist in a day
is 6. Find the probability that the receptionist receives 10 calls in a
particular day. (5 Marks)
3. What is the probability of getting 3 heads in a 5 tosses of a fair coin?
(5 Marks)
4. Construct a straight line from the given points below:
X 1.2 1.8 3.1 4.9 5.7 7.1 8.6 9.8
Y 4.5 5.9 7.0 7.8 7.2 6.8 4.5 2.7
Find the equation of the line of regression of Y on X using the points
given above (10 Marks)
5. The table below shows the weights to the nearest pound of boys and
girls in a certain school:
BOYS 64 53 67 55 58 77 57 56 51 76 68
GIRLS 57 49 62 51 50 55 48 52 42 61 57
Calculate Karl Pearson’s correlation coefficient of those boys and girls
in that school (15 Marks)
Page | 1
