The following stem and leaf display gives the performance of 23 students on a test out of 100:
tutor4helpyouT 3
The following stem and leaf display gives the performance of 23 students on a test out of 100:
2 1 3
3 0 3 4 4
4 1 1 2 2 7
5 0 5 5 5 8 9
6 4 6 7 7
7 1 2
1. The range is
A) 72
B) 51
C) 21
D) 50
2. The fifth best performing student got
A) 66
B) 64
C) 67
D) 59
3. --------- % OF THE STUDENTS GOT LESS THAN 50 IN THE TEST.
A) 43.5
B) 50
C) 47.8
D) 52.2
4. The mode is:
A) 55
B) 67
C) 42
D) 34
5 ----- % of the students got between 50 and 60 (I am not sure how to calculate the “between” as two answers can be right depending on how you understand the question? Please explain.
A) 26.1
B) 27.1
C) 22.7
D) 21.7
6. The variance
A) 15.41
B) 237.36
C) 51.14
D) 273.36
7. The coefficient of variation
A) 484.41
B) 13.38
C) 31.38
D) 269.32
Ashley has been keeping track of what she spends to eat out. The last weeks expenditures in rand for meals eaten out were 3,69; 3,95; 4,19; 8, 91; 5,49; 12.53; 5,66.
8. The mean:
A) 44.42
B) 6.35
C) 7.40
D) 5.36
9. The median
A) 8.91
B) 4.19
C) 5.49
D) 4.84
10. What is the shape of the distribution
A) Positive skew
B) Negative skew
C) Symmetrical
D)
11. The position of the first quartile
A) 2
B) 4
C) 3.95
D) 4.19
12. The third quartile
A) 6
B) 5.66
C) 8.91
D) 5
13. The position of the second quartile
A) 4
B) 3.5
C) 6
D) 5.49
14. The interquartile range
A) 5
B) 4.96
C) 8.91
D) 4
Use the following frequency table to answer the questions
Intervals |
xi |
fi |
Fi |
10-20 |
15 |
3 |
3 |
20-30 |
25 |
5 |
8 |
30-40 |
35 |
9 |
17 |
40-A |
45 |
13 |
C |
A-60 |
55 |
15 |
45 |
60-70 |
B |
9 |
54 |
70-80 |
75 |
14 |
68 |
80-90 |
85 |
12 |
80 |
15 What is the value of A?50
16 What is the value of B65
17. What is the value of the sample size (n)
A) 85
B) 80
C) 68
D) 90
18. What is the value of C?30
19 Calculate the first quartile of the data
A) 20
B) 42.3077
C) 31.5385
D) 25
20. Calculate the median of the data
A) 46
B) 50
C) 56.6667
D) 40
21. Calculate P60 of the data
A) 63.3333
B) 52.2222
C) 60
D) 48
22. The sum of the relative frequencies is always equal to 1
Given that P(A) = 0.7, P(B) = 0.6 and P(A and B) = 0.35 Show calculation:
23. P (A/ and B
A) 0.35
B) 0.05
C) 0.25
D) 0.3
24. P (A / B/ ) =
A) 0.875
B) 0.35
C) 0.4
D) 0.14
25. P (A/ or B/ ) =
A) 0.3
B) 0.7
C) 0.65
D) 0.05
26. If A and B are independent and P (A) = 0.3 and P (B) = 0.4, what is P (A and B)= 0.3*0.4 = 0.12
27. If A and B are mutually exclusive with P(A) = 0.6 and P(B) = 0.35, what is P(A and B)= 0
28. If P(A/B) = 0.7 with P (A) = 0.5 and P(B) = 0.6 determine P(B/A)=
A) 0.42
B) 0.5
C) 0.84
D) 0.7
A container has 3 red balls, 2 yellow balls and 4 blue balls. Now answer question 29-30
29. If 2 balls are drawn with replacement, what is the probability that you will get one red ball
A) 0.4444
B) 0.6667
C) 0.1481
D) 0
30. If 2 balls are drawn with replacement, what is the probability that you will get at least one red ball?
A) 0.4444
B) 0.5833
C) 0.5185
D) 1
31. Which of the following values cannot be a probability of an event?
A) 0.999
B) 8/6
C) 0.46
D) The square rout of 0.8
The following table contains the probability distribution for the number of traffic accidents (X) daily in a small town.
No of accidents (X) |
0 |
1 |
2 |
3 |
4 |
5 |
P(X) |
0.15 |
0.2 |
0.2 |
0.15 |
0.15 |
0.15
|
Determine
32. P (0 < X < 3)
A) 0.2
B) 0.4
C) 1.0
D) 0.55
33. P (X = 3)
A) 0.15
B) 0.4
C) 1.0
D) 0.55
34. P (X>3)
A) 0.30
B) 0.45
C) 0.40
D) 0.15
35. E (X)
A) 1
B) 2.4
C) 1.88
D) 2.88
36. Var (X)
A) 2.4
B) 1.66
C) 2.74
D) 2.88
Twenty five percent of the student houses in a certain area have a swimmingpool. Suppose 12 student houses in this area are selected at random
37. What is the expected number of houses without a swimming pool?9
38. What is the probability that at least two houses will have swimming pools?0.8416
39. What is the probability that at most nine houses will not have a swimming pool?
0.60932
40. What is the probability that at most 11 houses will not have swimming pools
A) 0.9683
B) 0.0317
C) 0
D) 0.8416
Given Z ~ N (0,1) – I will attach a table and also formulas
Question 41 to 60 is in the scan