Question

suppose that the frequency table below contains data on female life expectancy at birth in 73 randomly selected countries. use the table to determine the median life expectancy for females in these 73 countries. median = years (do not round)
age frequency
70 1
71 2
72 4
73 7
74 6
75 7
76 8
77 16
78 22

Explanation:

Step1: Calculate cumulative frequencies

Age	Frequency	Cumulative Frequency
71	2	1 + 2=3
72	4	3+4 = 7
73	7	7+7 = 14
74	6	14+6 = 20
75	7	20+7 = 27
76	8	27+8 = 35
77	16	35+16 = 51
78	22	51+22 = 73

Step2: Determine the position of the median

Since \(n = 73\) (an odd - numbered data set), the position of the median is \(\frac{n + 1}{2}=\frac{73+1}{2}=37\)th value.

Step3: Find the median

The cumulative frequency just greater than 37 is 51, which corresponds to an age of 77.

Answer:

77