The period of adolescence is lengthening in industrialized cultures such as in europe, the united states, and australia. adolescents are taking more time to finish their education and establish careers. the average age for a first marriage in the united states is now 29 for men and for women.

27

Explanation:

Nowadays, both men and women, from every strata, goes to school and is able to go to college (in some countries more than others), something that was unthinkable some decades ago were only the male son´s of the rich people went to the university.

This universalization of education (among other explanations, such as the elimination of  many predjuices envolving sexual relationships) , creates a generation that prefers to study, learn, experience (live!) and get extremely ready for working life as they can be before they ever think to get married, extending the average age of the first marriage.

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