When my mother was 40, I was 16. Now she is twice as old as I am. How old am I?

Question

A husband and wife have a combined age of 91. If husband is now twice as old as his wife was when he was as old as she is now.
How old are they now?

Answer 1

40 + x = (16 + x)*2 {x is the years that have passed by}
40 + x = 32 + 2x
x = 8
ie., When the mother is 48 the daughter will be 24 {after 8 years} and their age ratio will be 2:1.