When Pamela was 50 years old, her daughter was 2 times her son's age. Pamela would be twice her daughter's age when her son was 26 years old. How old would Pamela be when her son was 9 years old?

	Pamela	Daughter	Son
Before	50	2 u	1 u
Change	+ ?	+ ?	+ ?
After	2 p	1 p	26

The difference in the ages between Pamela and her daughter remains unchanged.

Difference in Pamela's and her daughter's ages at first
50 - 2 u = 2 p - 1 p
50 - 2 u = 1 p --- (1)

The difference in the ages between her daughter and her son remains unchanged.

Difference in her daughter's and her son's ages at first
2 u - 1 u = 1 p - 26
1 u + 26 = 1 p --- (2)

Make p the same.

(1) = (2)
50 - 2 u = 1 u + 26
1 u + 2 u = 50 - 26
3 u = 24

1 u = 24 ÷ 3 = 8

Age difference between Pamela and her son
= 50 - 1 u
= 50 - 8
= 42

Pamela's age when her son was 9 years old
= 42 + 9
= 51

Answer(s): 51