Technical Mathematics, Sixth Edition

21.9. CHAPTER 21 REVIEW PROBLEMS

Label each type of data as continuous, discrete, or categorical.

1. The life of certain radios. Continuous

2. The number of houses sold each day. Discrete

3. The colors of the cars at a certain dealership. Categorical

4. The sales figures for a certain product for the years 1970–80 are as follows:

   4.

   Year	Number Sold
   1970	1344
   1971	1739
   1972	2354
   1973	2958
   1974	3153
   1975	3857
   1976	3245
   1977	4736
   1978	4158
   1979	5545
   1980	6493

   Make an x-y graph of the sales versus the year.

5. Make a bar graph for the data of problem 4.

6. If we toss three coins, what is the probability of getting one head and two tails? 3/8

   5.

7. If we throw two dice, what chance is there that their sum is 8? 5/36

8. A die is rolled twice. What is the probability that both rolls will give a two? 1/36

9. At a certain factory, 72% of the workers have brown hair, 6% are left-handed, and 3% both have brown hair and are left-handed. What is the probability that a worker chosen at random will either have brown hair or be left-handed, or both? 0.75

10. What is the probability of tossing a five or a nine when two dice are tossed? 2/9

11. Find the area under the normal curve between the mean and 0.5 standard deviation to one side of the mean. 0.1915

12. Find the area under the normal curve between 1.1 standard deviations on both sides of the mean. 0.7286

13. Find the area ...