1. IQ is normally distributed with a mean of 100 and a standard deviation of 15. Suppose one individual is randomly chosen. LetX= IQ of an individual.

MENSA is an organization whose members have the top 2% of all IQs. Find the minimum IQ needed to qualify for the MENSA organization.

120

125

130

135

140

145

150

2. According to a study by Dr. John McDougall of his live-in weight loss program at St. Helena Hospital, the people who follow his program lose between six and 15 pounds a month until they approach trim body weight. Let's suppose that the weight loss is uniformly distributed. We are interested in the weight loss of a randomly selected individual following the program for one month.

P(7 <x< 13 |x> 9) = __________.

3/5

5/9

2/3

2/5

none of the other

3. X= the number of days per week that 100 clients use a particular exercise facility.

x	Frequency
0	3
1	12
2	33
3	28
4	11
5	9
6	4

The 80thpercentile is _____

5

4

3

80

4. Suppose that a category of world-class runners is known to run a marathon (26 miles) in an average of 145 minutes with a standard deviation of 14 minutes. Consider 49 of the races. Let \overline{X}X be the average of the 49 races.

Find the 80thpercentile for the average of these 49 marathons.

199.47

170.84

150.89

146.68

130.78