Probability & Statistics 1 — Variant 2
A Level Mathematics · 9709/52 · May/June 2022
Questions
6 of 7 questions shown here, checked against the paper. The others are in the PDF above — they contain diagrams or maths we could not yet verify, and we would rather show you the original than a transcription we are not sure of.
1
[3]
For values of the variable , it is given that and . Find the value of .
2
A fair -sided die has the numbers on its faces. The die is rolled twice. The random variable denotes the sum of the two numbers obtained.
2(a)
[3]
Draw up the probability distribution table for .
2(b)
[3]
Find and .
4
The weights, in kg, of bags of rice produced by Anders have the distribution .
4(a)
[3]
Find the probability that a randomly chosen bag of rice produced by Anders weighs between and kg. The weights of bags of rice produced by Binders are normally distributed with mean kg and standard deviation kg. In a random sample of of these bags, weighed more than kg.
4(b)
[4]
Find the value of .
5
In a large college, of the students do not play any musical instrument, play exactly one musical instrument and the remainder play two or more musical instruments. A random sample of students from the college is chosen.
5(a)
[3]
Find the probability that more than of these students play at least one musical instrument. A random sample of students from the college is now chosen.
5(b)
[5]
Use an approximation to find the probability that fewer than of these students play exactly one musical instrument.
6
6(a)
[1]
Find the number of different arrangements of the letters in the word CROCODILE.
6(b)
[3]
Find the number of different arrangements of the letters in the word CROCODILE in which there is a at each end and the two s are not together.
6(c)
[3]
Four letters are selected from the letters in the word CROCODILE. Find the number of selections in which the number of s is not the same as the number of s.
6(d)
[3]
Find the number of ways in which the letters in the word CROCODILE can be divided into three groups, each containing three letters, if the two s must be in different groups.
7
Hanna buys hollow chocolate eggs that each contain a sweet. The eggs look identical but Hanna knows that contain a red sweet, contain an orange sweet and contain a yellow sweet. Each of Hanna's three children in turn randomly chooses and eats one of the eggs, keeping the sweet it contained.
7(a)
[4]
Find the probability that all eggs chosen contain the same colour sweet.
7(b)
[2]
Find the probability that all eggs chosen contain a yellow sweet, given that all three children have the same colour sweet.
7(c)
[3]
Find the probability that at least one of Hanna's three children chooses an egg that contains an orange sweet.
Published by Cambridge Assessment International Education. Reproduced for study use.