The Youngs have been married for 31 years. Their son is 25 and their daughter is 19. In what year were they married? In what year were their daughter and son born?
First of all, we have to assume that this question is talking about this year -- in other words it is this year that they have been married 31 years.
If that is that case, they you just have to subtract 31 from this year. 2010-31 = 1979. So they were married in 1979. However, if their anniversary has not come yet this year then they were married in 1978 and when their anniversary gets here, they will have been married for 32 years.
You figure out their daughter's birth year the same way. 2010 - 19 = 1991.
In what year were they married?
2010-31=1979 (assuming their anniversary was before April 26, 2010)
In what year was their daughter born?
2010-19= 1991 (again assuming her birthday was before April 26, 2010)
In what year was their son born?
2010-25= 1985 (you subtract the age from the current year to get his current age)
(now if you had more information on the actual month of marriage and birthday's we could then figure out the actual anniversary by months and the chronological age)
Young.s married 31 years back.The present year is 2010. So they married 2010-31 = 1979.
Their son is 25.Therefore he was born 25 years ago. So the son was born in (2010-25) = 1985.
Their daughter is 19. She was, therefore, born 19 years back. So she was born in (2010-19) = 1991.