1. The acidity or alkalinity of a solution is measured using pH. A pH less than 7 is acidic; a pH greater than 7 is alkaline. The accompanying data represent the pH in samples of bottled water and tap water. Complete parts (a) and (b).

(a) Compute the mean, median, and mode pH for each type of water in table (a) only.

For tap water, the mean pH is___________ (Round to the nearest thousandth as needed.)

For tap water, the median pH is____________(Round to the nearest thousandth as needed.)

Select the correct choice below and fill in any answer boxes in your choice.

A. For tap water, the mode pH is____________(Round to the nearest thousandth as needed. Use a comma to separate answers asneeded.)

B. There is no mode.

For bottled water, the mean pH is___________(Round to the nearest thousandth asneeded.)

For bottled water, the median pH is_________(Round to the nearest thousandth asneeded.)

Select the correct choice below and fill in any answer boxes in your choice.

A. For bottled water, the mode pH is__________(Round to the nearest thousandth as needed. Use a comma to separate answers asneeded.)

B. There is no mode.

(b) Suppose the pH of 7.22 in tap water was incorrectly recorded as 2.72,

as seen in table (b).

How does this affect the mean? the median? What property of the median does this illustrate?

If the pH of 7.22 in tap water was incorrectly recorded as 2.72, the mean pH is________(Round to the nearest thousandth as needed.)

If the pH of 7.22 in tap water was incorrectly recorded as 2.72, the median pH is________ .

(Round to the nearest thousandth as needed.)

What property of the median does this illustrate?

A.It illustrates that the median divides the bottom 50% of the data from the top 50%.

B.It illustrates resistance of the mean.

C.It does not illustrate any property of the median.

D.It illustrates resistance of the median.

1: Data Table

(a)

							Full data set
Tap	7.64	7.45	7.47	7.52	7.68	7.93
7.45	7.22	7.56	7.47	7.52	7.47
Bottled	5.15	5.09	5.26	5.20	4.90	5.23
5.28	5.26	5.13	5.26	5.22	5.24

(b)

Tap	7.64	7.45	7.47	7.52	7.68	7.93
7.45	2.72	7.56	7.47	7.52	7.47
Bottled	5.15	5.09	5.26	5.20	4.90	5.23
5.28	5.26	5.13	5.26	5.22	5.24

2: Data Table

(a)

							Full data set
Tap	7.64	7.45	7.47	7.52	7.68	7.93
7.45	7.22	7.56	7.47	7.52	7.47
Bottled	5.15	5.09	5.26	5.20	4.90	5.23
5.28	5.26	5.13	5.26	5.22	5.24

(b)

Tap	7.64	7.45	7.47	7.52	7.68	7.93
7.45	2.72	7.56	7.47	7.52	7.47
Bottled	5.15	5.09	5.26	5.20	4.90	5.23
5.28	5.26	5.13	5.26	5.22	5.24

2. An insurance company crashed four cars of the same model at 5 miles per hour. The costs of repair for each of the four crashes were $431, $445, $478, and $247.

Compute the mean, median, and mode cost of repair.

Compute the mean cost of repair. Select the correct choice below and, if necessary, fill in the answer box to complete your choice.

A.The mean cost of repair is $__________(Round to the nearest cent as needed.)

B. The mean does not exist.

Compute the median cost of repair. Select the correct choice below and, if necessary, fill in the answer box to complete your choice.

A. The median cost of repair is $__________(Round to the nearest cent as needed.)

B. The median does not exist.

Compute the mode cost of repair. Select the correct choice below and, if necessary, fill in the answer box to complete your choice.

A. The mode cost of repair is $________(Round to the nearest cent as needed.)

B.The mode does not exist.