Study text: "Essential Mathematics and Statistics for Science", 2nd Edition,

G Currell & A A Dowman, Wiley-Blackwell, 2009

G Currell & A A Dowman, Wiley-Blackwell, 2009

- Single measurements of the COD (chemical oxygen demand) of a river were made by each of 20 students and recorded as below (units of mg L
^{-1}):64.8 64.7 65.0 67.5 63.9 65.2 66.8 67.2 65.1 67.7 66.9 66.1 67.1 67.3 64.9 64.6 64.2 68.2 68.2 64.4

Which would be the best type of data analysis to perform first? Select**ONE**option.

(You do NOT need to perform any analysis of the data)- Draw a scatter plot
- Calculate the mean and standard deviation
- Draw a box and whisker plot
- Draw a histogram or stem and leaf plot

- The frequency column graph shows the numbers of trees with heights (m) within the given height ranges:

Given the available information, perform a simple calculation to estimate the mean height of the trees.- 2.40 m
- 2.44 m
- 2.54 m
- 2.64 m

- The frequency column graph shows the numbers of trees with heights (m) within the given height ranges:

With reference to the equation, checkThe equation to estimate the mean height

of the*n*trees is given by:**ALL**of the following statements that are correct.

(Click here for the Video Answer) - The following graphs show the numbers of trees with heights (m) within given ranges.

Graph A is a frequency graph and graph B is a probability density histogram.

Check

Graph A

Graph B**ALL**of the following statements that are completely correct.

(Click here for the Video Answer) - The probability density histogram shows the relative probabilities of recording specific experimental values when measuring a true blood alcohol level of 77 mg per 100 mL:

From the graph, estimate the probability that a single experimental measurement will give a value that is above 80. Select the closest value- 0.12
- 0.09
- 0.07
- 0.04

- The probability density histogram shows the normal distribution probabilities of recording specific experimental values when measuring a true blood alcohol level of 77 mg per 100 mL:

If the probability of recording a measurement below 79 is 0.8413, calculate the probability (to 2 sf) of recording a value between 75 and 79.- 0.68
- 0.67
- 0.64
- 0.50