Q1. Consider the following stem and leaf plot:
Stem Leaf
1 0, 2, 5, 7
2 2, 3, 4, 4
3 0, 4, 6, 6, 9
4 5, 8, 8, 9
5 2, 7, 8
Suppose that a frequency distribution was developed from this, and there were 5 classes (10- under 20, 20-under 30, etc.). What is the cumulative frequency for the 30-under 40 class interval?
A. 5
B. 9
C. 13
D. 14
Q2. Chebyshev's Theorem says that the number of values within 3 standard deviations of the mean will be _______.
A. at least 75%
B. at least 68%
C. at least 95%
D. at least 89%
Q3. A commuter travels many kilometres to work each morning. She has timed this trip 5 times during the last month. The time (in minutes) required to make this trip was 44, 39, 41, 35 and 41. The mean time required for this trip was 40 minutes. What is the variance for this sample data?
A. 8.8
B. 11
C. 0
D. 3
Q4. Meagan Davies manages a portfolio of 200 common stocks. Her staff classified the portfolio stocks by 'industry sector' and 'investment objective'.
Investment Industry Sector
Objective Electronics Airlines Healthcare Total
Growth 100 10 40 150
Income 20 20 10 50
Total 120 30 50 200
If a stock is selected randomly from Meagan's portfolio, P(Growth|Healthcare) = _____.
A. 0.25
B. 0.40
C. 0.20
D. 0.80
Q5. Adam Shapiro, Director of Human Resources, is exploring employee absenteeism at Plain Power Plant. Ten per cent of all plant employees work in the finishing department; 20% of all plant employees are absent excessively; and 7% of all plant employees work in the finishing department and are absent excessively. A plant employee is selected randomly; F is the event 'works in the finishing department'; and A is the event 'is absent excessively'. P(A|F) = _____________.
A. 0.37
B. 0.70
C. 0.13
D. 0.35