Practice Paper Statistics 1 (Edexcel International A Level Maths: Pure 4)

Practice Paper Questions

1a
Sme Calculator
4 marks

Three events A comma B and C, are such that B and C are mutually exclusive and A and C are independent. straight P open parentheses A close parentheses equals 0.3P open parentheses B close parentheses equals 0.45   and  straight P open parentheses C close parentheses equals 0.1.

Given that P open parentheses open parentheses A union B union C close parentheses to the power of apostrophe close parentheses equals 0.43, draw a Venn diagram to show the probabilities for events A comma B, and C.

 

1b
Sme Calculator
3 marks

Find:

(i)
P open parentheses B vertical line A close parentheses

(ii)
P open parentheses A vertical line B to the power of apostrophe close parentheses

(iii)
P open parentheses A vertical line open parentheses B U C close parentheses close parentheses

Did this page help you?

2a
Sme Calculator
4 marks

An A level music teacher is collecting data on the number of hours his students spend rehearsing their  final piece, h, and the number of mistakes made in their exam, m.  He calculates the following summary data of ten of his students.

sum h space equals space space 2194           sum m space equals space space 68         sum h squared equals 496676          sum m squared equals 544          sum h m equals space 13960

(i)
Show that the product moment correlation coefficient for these data is space r equals negative 0.858 , correct to 3 decimal places. 
(ii)
State, giving a reason, whether or not the product moment correlation coefficient is consistent with the use of a linear regression model.
2b
Sme Calculator
3 marks

The music teacher calculates the equation of the regression line of m on h to be  m equals a space plus space b h.

Show that b equals space minus 0.0626 space correct to 3 significant figures and find the value of a.

2c
Sme Calculator
2 marks
(i)
Give an interpretation of the value of a in context.
(ii)
By considering your answer to part (i), or otherwise, give a limitation to the linear regression model.

Did this page help you?

3a
Sme Calculator
3 marks

Tim has just moved to a new town and is trying to choose a doctor’s surgery to join, HealthHut or FitFirst. He wants to register with the one where patients get seen faster. He takes of sample of 150 patients from HealthHut and calculates the range of waiting times as 45 minutes and the variance as 121 minutes².

An outlier is defined as a value which is more than 2 standard deviations away from the mean.

Prove that the sample contains an outlier.

3b
Sme Calculator
2 marks

Tim finds out that the outlier is a valid piece of data and decides to keep the value in his sample.

Which pair of statistical measures would be more appropriate to use when using the sample to compare the doctor’s surgeries: the mean and standard deviation or the median and interquartile range? Give a reason for your answer.

3c
Sme Calculator
1 mark

The box plots below show the waiting times for the two surgeries.q4b-very-hard-2-3-working-with-data-edexcel-a-level-maths-statistics

Given that there is only one outlier for HealthHut, label it on the box plot with a cross (×).

3d
Sme Calculator
4 marks

Compare the two distributions of waiting times in context.

Did this page help you?

4a
Sme Calculator
3 marks

An advertisement for a charity is shown on TV at the same time every weekday for four weeks.  To assess the impact of the advert, the charity’s manager decides to record the number of donations the charity receives each day in the hour after the advert is broadcast.  The results are listed below: 

                                    21       27       24       31       17

                                    22       25       26       27       9

                                    32       29       25       24       40

                                    23       22       19       12       14 

Represent these data in a sorted stem-and-leaf diagram.

4b
Sme Calculator
2 marks

The manager decides that the advert is not cost effective unless the median number of donations per day in the hour after broadcast is at least 25. Determine whether the manager should continue to run the TV advert.

4c
Sme Calculator
1 mark

Give one advantage of using a stem-and-leaf diagram as opposed to grouping the data into a frequency table.

Did this page help you?

5
Sme Calculator
4 marks

A pharmacy sells face masks in a variety of sizes.  Their sales over a week are recorded in the table below:

  Kids Adults
Size Small Large S M L XL
Frequency f 29 4 8 24 15 4

(i)

Write down the mode for this data.

(ii)
Explain why, in this case, the mode from part (i) would not be particularly helpful to the shop owner when reordering masks.

(iii)
Given that the shop is open every day of the week, calculate the mean number of masks sold per day.

Did this page help you?

6a
Sme Calculator
3 marks

Rosco is a somewhat inept rural county sheriff who frequently finds himself involved in car chases with well-meaning local entrepreneurs.  During any given car chase, Rosco inevitably runs into one of three obstacles – a damaged bridge (with probability 0.47), an oil slick (with probability 0.32), or a pigpen at the end of a dead-end road.

If he encounters a damaged bridge there is a 25% chance that he will make it across safely; otherwise he lands in the river and ends up covered in mud.  If he encounters an oil slick there is a 40% chance that his car will spin around and he will end up continuing his hot pursuit in the wrong direction; otherwise he goes off the road into a farm pond and ends up covered in mud.  If he encounters a pigpen at the end of a dead-end road there is a 15% chance he will stop his car in time; otherwise he drives into the muddy end of the pigpen while the pigs sit at the other end laughing.  If he drives into the muddy end of a pigpen there is a 20% chance he will only end up covered in mud; otherwise he ends up covered in mud and other things that are found in pigpens.

Draw a tree diagram to represent this information.

6b
Sme Calculator
3 marks

Find the probability that in the course of a randomly chosen car chase

(i)
Rosco ends up covered in mud

(ii)
Rosco ends up covered in mud, but only in mud.
6c
Sme Calculator
3 marks

Given that Rosco ends up covered in mud in the course of a randomly chosen car chase, find the probability that he didn’t encounter an oil slick. Give your answer as an exact value.

6d
Sme Calculator
2 marks

In the course of a particular day Rosco finds himself engaged in three separate car chases with well-meaning local entrepreneurs.  The car chases may be considered to be independent events.

Determine the probability that on that day Rosco will not end up covered in other things that are found in pigpens.

Did this page help you?

7a
Sme Calculator
1 mark

A spinner has three sectors labelled 0, 1 and 2. Let X be the random variable denoting the number the spinner lands on when spun. The probability distribution table for X is shown below: 

bold italic x 0 1 2
straight P open parentheses straight X equals x close parentheses a b c

 

It is given that straight E open parentheses X close parenthesesequals 1.1 and Var open parentheses X close parentheses equals 0.89

Write down the value of straight E open parentheses X squared close parentheses.

7b
Sme Calculator
4 marks

Find the values of a comma b space and space c.

7c
Sme Calculator
4 marks

Susie spins the spinner twice and adds together the two numbers to calculate her score, S. Tommy spins the spinner once and doubles the number to calculate his score, T. Each spin of the spinner is independent of all other spins. 

Draw up the probability distribution table for:

(i)
S,
(ii)
T.
7d
Sme Calculator
1 mark

Which player is most likely to get a score that is bigger than 2?

Did this page help you?

8a
Sme Calculator
5 marks

A biased four-sided dice is rolled and the number that it lands on is denoted X  which has probability distribution shown below.

x negative 2 negative 1 1 half 2
P open parentheses X equals x close parentheses a b c c

The cumulative distribution function of X is given by:

x negative 2 negative 1 1 half 2
straight F open parentheses x close parentheses 1 over 7 2 over 5 d e

Find the values of a comma b comma c comma d comma spaceand e.

8b
Sme Calculator
2 marks

Saskia and Tamara place a game by rolling the dice. Saskia’s score is the number the dice lands on and Tamara’s score is the reciprocal of that number.

Find the probability that Saskia’s score is bigger than Tamara’s score.

Did this page help you?

9a
Sme Calculator
3 marks

Paul enjoys solving sudoku puzzles. The lengths of time he spends on sudokus in a week are normally distributed with a mean of 2048 minutes and a standard deviation of 64 minutes.

Find the probability that in a given month Paul spends less than 1945 minutes solving sudoku puzzles.

9b
Sme Calculator
4 marks

Estimate the number of weeks in a year that Paul spends between 2019 and 2091 minutes solving sudoku puzzles.

9c
Sme Calculator
4 marks

Assuming it takes Paul exactly 10 minutes to solve any sudoku puzzle, find the greatest number, n, of sudoku puzzle such that the probability of Paul solving less than n puzzles in a week is less than 0.01.

Did this page help you?