The table provides data for cellular phone usage for 1000 respondents of different age groups. The hypothesis that the proportions using cellular phones are same for different age groups will be tested using chi-square analysis. The degrees of freedom for this analysis will be

Cellular Phone Usage	18-24 Year	25-54 Year	55-64 Year	≥ 65 Year	Total
Yes	80	50	70	50	250
No	170	200	200	180	750
Total	250	250	270	230	1000