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|| Problems
At present John's age is 30% of his father's age. Twenty years from now, Jon's age will by 58% of his father's age. How old are they?
Solution:
Age at Present
Age 20 years from the present
Father
F
F+20
Son(John)
J
J+20
Relationship
\(J = 0.30 F\)
J+20 = 0.58 (F+20)
\(J+20 = 0.58F + 11.6\)
\(0.30F+20 = 0.58F + 11.6\)
\(F = 30\)
\(J = 0.30(30) = 9\)
Thus, the father's age at present is 30 years old and the son (John) is 9 years old.