Question
The current age of Derek is twice that of Eve. 7 years
from now, Derek's age will be 1.5 times the age of Fred at that time. If Eve is 5 years younger than Fred, determine the current age of Derek.Solution
Let the present age of Eve be ‘e’ years. Thus, the present age of Derek = ‘2e’ years. Let the present age of Fred be ‘e + 5’ years. ATQ, (2e + 7) = 1.5 × (e + 5 + 7), Or, 2e + 7 = 1.5e + 18, Or, 2e – 1.5e = 18 - 7, Or, e = 11, Therefore, 2e = 22. Therefore, the current age of Derek = 22 years.
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