Relative Frequency

1. Assume the resting heart rates for a sample of individuals are normally distributed with a mean of 70 and a standard deviation of 15. Use the 68-95-99 rule to find the following quantities:

a. Percentage of rates less than 70 = 50%

b. Percentage of rates less than 55 = 16%

c. Relative frequency of rates less than 40 = 2.5%

d. Percentage of rates less than 85 = 84%

e. Relative frequency of rates less than 100 = 97.5%

f. Percentage of rates greater than 85 = 16%

g. Percentage of rates greater than 55 = 84%

h. Relative frequency of rates greater than 40 = 97.5%

i. Percentage of rates between 55 and 85 = 68%

j. Percentage of rates between 70 and 100 = 47.5%

2. Here are the results of four of your test:

| | Your score | Mean |Standard Deviation |
|Math (out of 100) |70 |80 |3.3 |
|QM (out of 20) |20 |18 |3 |
|RM (out of 100) |66 |75 |5 |
|History (out of 30) |28 |20 |3.5 |

a. Present all four results on a standardized normal curve. Be sure to present the calculations for each test.

*Math: (70 - 80) / 3.3 = -3.03

*QM: (20 - 18) / 3 = 0.67

*RM: (66 - 75) / 5 = -1.8

*History: (28 - 20) /3.5 = 2.29

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Math RM QM History

b. What is the percentage of people