3. A social worker was interested in finding the effect of education among women on their married life. The data given below are the levels of their education and the number of years they remained married to their first husband. Test at the 5% level of significance the null hypothesis that the factors “education” and “marriage” are independent.

<10 10–< 20 20–<30 ≥30 Total High school 37 31 20 12 100 Undergraduate degree 25 40 15 20 100 Graduate degree 20 25 35 20 100 Professional degree 10 8 30 52 100 Total 92 104 100 104 400