Question

old by years Interval	Frequency
35-37	two
32-34	three
29-31	five
26-28	Six
23-25	four
20-22	five
17-19	nine
14-16	Sixteen

Calculate the above when Passport first used

1- what is the shape of the old distribution?

2- Which accurate statements can describe the relationship between the mean and median old?

1. he mean and median are the same
2. The mean is bigger than the median
3. The mean is less than the median

3- Calculate percentile rank corresponding to the old of 30? Answer by utilizing interpolation

Answer 1

1.

From the histogram, shape of the old distribution is positively skewed.

2.

Interval	Mid value (x)	Frequency (f)	xf	Cumulative frequency (< type)
14-16	15	16	240	16
17-19	18	9	162	25
20-22	21	5	105	30
23-25	24	4	96	34
26-28	27	6	162	40
29-31	30	5	150	45
32-34	33	3	99	48
35-37	36	2	72	50
		50	1086
Mean=	21.72
N=	50
N/2=	25
Median class=	16.5-19.5
Lower class boundary=l=	16.5
Median Class width=c=	3
Cumulative frequency upto 16.5=Fl=	16
Frequency of median class=f0=	9

Option: B. The mean is bigger than the median.

3.

Cumulative frequency corresponding 30=47, then percentile rank=(47/50)*100=94%.