When Jen was 26 years old, her daughter was 2 times her son's age. Jen would be twice her daughter's age when her son was 20 years old. How old would Jen be when her son was 6 years old?

	Jen	Daughter	Son
Before	26	2 u	1 u
Change	+ ?	+ ?	+ ?
After	2 p	1 p	20

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

Difference in Jen's and her daughter's ages at first
26 - 2 u = 2 p - 1 p
26 - 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 - 20
1 u + 20 = 1 p --- (2)

Make p the same.

(1) = (2)
26 - 2 u = 1 u + 20
1 u + 2 u = 26 - 20
3 u = 6

1 u = 6 ÷ 3 = 2

Age difference between Jen and her son
= 26 - 1 u
= 26 - 2
= 24

Jen's age when her son was 6 years old
= 24 + 6
= 30

Answer(s): 30