CHAPTER 3 EXERCISES 1. The number of incorrect answers on true-false test for random sample student of 10 students are 51. 63, 80, 75, 82, 63, 81, 63, 76 and 02. Find the. (a) mean (b) median (c) mode 2. A student got the following grades in 7 different subjects, 1.25 for mathematics; 1.50 for physics; 2.00 for English; 3.00 for chemistry; 2.75 for statistics; 1.25 for physical education; and 2.50 for history. Compute the weighted mean grade if the weight for the 7 subjects are 3, 5, 3. 4, 3, 2, and 3 respectively. 3. A food inspector examined a random sample of 5 cans of certain brand of canned goods to determine the percent of foreign impurities. The following data were recorded. 1.2, 1.8. 0.8, 1.3 and 1.8. find the measure of central tendency. (a) mean (b) median (c) mode 4. The reactions of a random sample of 10 rats to stimulant were recorded as 4.0, 2 6, 3.2. 4.1, 2.3, 3.5, 2 2, 2 3. 2.6 and 4.2 seconds. Calculate the: (a) mean (b) median (c) mode 5. Below is the frequency distribution of final examination scores in Basic math for BSEt. 1- 5. Complete the table and compute for the mean, median and mode. Class Interval Frequency 50-54 65-59 80-84 85-80 19 70-74 13 75-79 80-846. In determining the refractive index of a volatile oil, 40ovserbatons were made at 22-C and the following values were recorded. Compute for the mean, median and mode. Class Interval Frequency 1.57 - 1.59 4 1.54 - 1.56 9 1.51 - 1.53 14 1.48 - 1.50 10 1.45 - 1.47 3 7. The blood pressures of a group of 15 individuals were taken and recorded as follows 125 119 115 120 119 110 120 119 115 120 115 10 125 110 124 Calculate the weighted arithmetic mean. 8. A bus is design to carry a maximum load of 2,100 lbs. is it over loaded if at one time, it is loaded with 9men whose mean weight is 182 lbs. and 6 women whose mean weight is 131 lbs.? 9. A consumer testing company performed 6 test runs as the number of kilometers per lite consumed by the 3 latest passenger jeepney models. The results were as follows: (a) Jeep 1 7.2, 6.9, 8.5, 9.6, 10.8, 11.2 (b) Jeep 2 9.2, 11.90, 7.5, 8.1, 6.2, 9.0 (c) Jeep 3 8.6, 10.9, 11.0, 9.0, 6.1, 8.1 Which passenger Jeepney model performed best in the test 10. A study conducted on the records of the Land Transportation Office (LTO) shows 20 drivers belonging to 18-23 age groups received traffic violation receipt (TVR) for the first quarter of the year. The 4, 2, 3, 1, 0, 1, 2, 4, 4, 2, 0, 0, 2, 1, 3, 4, 4, 3, 2, 1. Find the mode. Describe the kind of drivers in this particular age group based on the recorded data.11. In determining the refractive index of a volatile oil, 40ovserbatons were made at 22 C and the following values were recorded. Compute for the mean, median and mode. 12. The following is the frequency distribution of the weights of 100 expectant mothers admitted in a hospital during a week Weight (Ibs) frequency 150-159 3 140-149 12 130-139 19 120-129 28 110-119 26 100-109 10 90-99 2 100 (a). Draw a histogram of the distribution. (b). Draw a frequency polygon of the distribution. 13. On Six consecutive days, the maintenance department received 7, 10, 9, 11, 13 and 7 service calls. Calculate s. 14. Find the variance, given: x = 457, x2 = 15,345, n = 14. 15. Here are the scores of Miss Universe candidate from 8 judges: 8.95, 8.60, 9.60, 9.10, 9.15, 9.25, 8.85 and 9.30 Find the standard deviation of the scores. 16. In a statistics class are 20 masscom students, 18 commerce students, and 12 science students. If the masscom students average 68 in the test, the commerce students averaged 75, and science students average 86 find the standard deviation of the scores
