- Will is 4 years older than Phil. Three years from now, Will will be
twice as old as Phil was last year. Find their present ages.
SOLUTIONS:
- Letx¼the son’s age and 6x¼the father’s age; thenxþ 9 ¼the son’s
age and 6xþ 9 ¼the father’s age in 9 years.
3 ðxþ 9 Þ¼ 6 xþ 9
3 xþ 27 ¼ 6 xþ 9
3 x 6 xþ 27 ¼ 6 x 6 xþ 9
3 xþ 27 ¼ 9
3 xþ 27 27 ¼ 9 27
3 x¼ 18
31 x
31
¼
18
3
x¼ 6 ðson’s ageÞ
6 x¼ 6 6 ¼ 36 ðfather’s ageÞ
- Letx¼daughter’s age and 2x¼mother’s age; thenx 20 ¼the
daughter’s age and 2x 20 ¼the mother’s age 20 years ago.
4 ðx 20 Þ¼ 2 x 20
4 x 80 ¼ 2 x 20
4 x 2 x 80 ¼ 2 x 2 x 20
2 x 80 ¼ 20
2 x 80 þ 80 ¼ 20 þ 80
2 x¼ 60
21 x
21
¼
60
2
x¼ 30 ðdaughter’s age)
2 x¼ 2 30 ¼ 60 ðmother’s age)
126 LESSON 12 Solving Age Problems