Question

The number of calls received per week by the clients services of a cell phone company over the last 40 weeks are given as follows:

63 74 42 65 51 54 36 56 68 57 62 64 76 67 79 61 81 77 59 38 84 68 71 94 71 86 69 75 91 55 48 82 83 54 79 62 68 58 41 47

a) Prepare a frequency distribution (table) and histogram for the data. Specify the number of bins, the width of the bins and the bins limits. (8 marks)

b) Describe the histogram that you have obtained. Justify your answer. (2 marks)

Answer 1

Result:

The number of calls received per week by the clients services of a cell phone company over the last 40 weeks are given as follows:

63 74 42 65 51 54 36 56 68 57 62 64 76 67 79 61 81 77 59 38 84 68 71 94 71 86 69 75 91 55 48 82 83 54 79 62 68 58 41 47

a) Prepare a frequency distribution (table) and histogram for the data. Specify the number of bins, the width of the bins and the bins limits. (8 marks)

minimum	36
maximum	94
range	58

Let the number of bins = 6, therefore the width of the bins = 58/6 = 9.6 = 10 (approximately)

	Number of calls received			cumulative
	Clalss limit	frequency	percent	frequency	percent
	36-45	4	10.0	4	10.0
	46-55	6	15.0	10	25.0
	56-65	10	25.0	20	50.0
	66-75	9	22.5	29	72.5
	76-85	8	20.0	37	92.5
	86-95	3	7.5	40	100.0
		40	100.0

Histogram 12 10 10 9 8 8 6 Frequency 02 4 4 3 N 0 36-45 56-65 76-85 46-55 66-75 86-95 Number of calls received

b) Describe the histogram that you have obtained. Justify your answer. (2 marks)

The shape of the distribution is nearly bell shaped. There is not much skewness in the data. The data is peaked at the class limit 56 to 65. The data are centered around 56 to 75.