posted by Ganelle .
a male born in 1975 does not want his future wife to outlive him. What should be the year of birth for his wife so that they both can be expected to die in the same year?
Find M(y)+F(y) to get the formula for life expectancy of a person born in year y
F (1975) - M (1975)
M(y) = 0.16252y - 251.91
F(y) = 0.18268y - 284.98