Edexcel GCE Statistics S1 Advanced Advanced Subsidiary 6683 4

1. In a regression equation, the correlation coefficient between two variables is r=−0.9r
= -0.9r=−0.9. What does this indicate about the relationship between the variables?
A. Strong positive linear relationship
B. Strong negative linear relationship
C. Weak negative linear relationship
D. No relationship
Answer: B) Strong negative linear relationship
Rationale: A correlation coefficient of r=−0.9r = -0.9r=−0.9 indicates a strong negative
linear relationship between the two variables.

2. Which of the following is true for a Poisson distribution?
A. It has a fixed mean of 1.
B. It is discrete and models the number of events in a fixed interval.
C. It is always symmetrical.
D. It can only be used for continuous data.
Answer: B) It is discrete and models the number of events in a fixed interval.
Rationale: The Poisson distribution is used for modeling the number of events in a fixed
interval of time or space.

3. The variance of a dataset is 25. What is the standard deviation?
A. 5
B. 25
C. 10
D. 100
Answer: A) 5
Rationale: Standard deviation = √(variance) = √25 = 5.

4. If the correlation coefficient between two variables is 0.8, what does this indicate?
A. A strong positive linear relationship
B. A strong negative linear relationship
C. No linear relationship
D. A weak negative linear relationship
Answer: A) A strong positive linear relationship
Rationale: A correlation coefficient of 0.8 indicates a strong positive relationship
between the variables.

5. What is the total number of outcomes when flipping 3 coins?
A. 4
B. 6
C. 8
D. 10
Answer: C) 8
Rationale: Each coin has two possible outcomes (Heads or Tails), so for 3 coins, the
total number of outcomes is 23=82^3 = 823=8.

6. The data set consists of the values: 3, 4, 6, 7, 9. What is the range?
A. 6
B. 5

, C. 4
D. 3
Answer: B) 6
Rationale: The range is the difference between the maximum and minimum values:
9−3=69 - 3 = 69−3=6.

7. What is the probability of getting at least one "6" when rolling two dice?
A. 11/36
B. 1/6
C. 5/36
D. 7/36
Answer: A) 11/36
Rationale: The probability of getting at least one "6" is the complement of the
probability of not getting a "6" on both dice, which is 1−(5/6)2=11/361 - (5/6)^2 =
11/361−(5/6)2=11/36.

8. Which of the following distributions is used to model the number of successes in a
fixed number of trials?
A. Normal distribution
B. Exponential distribution
C. Poisson distribution
D. Binomial distribution
Answer: D) Binomial distribution
Rationale: The binomial distribution models the number of successes in a fixed number
of independent trials.

9. The value of a statistic is normally distributed with mean 10 and standard deviation
3. What is the z-score corresponding to the value 13?
A. 1
B. 0.5
C. 0.33
D. 2.5
Answer: A) 1
Rationale: Z-score = X−μσ=13−103=1\frac{X - \mu}{\sigma} = \frac{13 - 10}{3} =
1σX−μ=313−10=1.

10. What is the mean of the following data set: 1, 2, 2, 4, 5?
A. 3
B. 2.5
C. 2
D. 4
Answer: A) 3
Rationale: The mean is 1+2+2+4+55=3\frac{1 + 2 + 2 + 4 + 5}{5} =
351+2+2+4+5=3.

11. A sample consists of the following values: 4, 7, 10, 13, 16. What is the median of
the sample?
A. 7
B. 10
C. 13