A father is now three times as old as his son. Five years back, he was...
Let son's age be x years. Then, father's age = (3x) years.
Five years ago, father's age = (3x - 5) years and son's age = (x - 5) years.
So, 3x - 5 = 4 (x - 5)
3x - 5 = 4x - 20
x = 15.
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A father is now three times as old as his son. Five years back, he was...
Given information:
- The father is now three times as old as his son.
- Five years back, the father was four times as old as his son.
Let's assume the current age of the son as "x" years.
According to the first statement, the current age of the father is three times that of the son, so the current age of the father is 3x years.
Five years back, the age of the son was x - 5 years, and the age of the father was 3x - 5 years.
According to the second statement, the father was four times as old as his son at that time, so we can write the equation:
3x - 5 = 4(x - 5)
Solving the equation:
3x - 5 = 4x - 20
3x - 4x = -20 + 5
-x = -15
x = 15
Therefore, the current age of the son is 15 years, which matches option B.
Explanation:
To find the age of the son, we need to solve the equation based on the given information. By assuming the current age of the son as "x" years, we can establish a relation between the ages of the father and son. Using this relation, we can derive an equation to solve for the value of "x". Solving the equation gives us the age of the son, which is 15 years.