New Enroll in RBI Grade B New Batch - Starts on May 21

    Question

    The sum of the ages of a father and his son is 50 years.

    After 10 years, the father will be four times as old as the son. What are their current ages?
    A Father is 46, son is 4 Correct Answer Incorrect Answer
    B Father is 45, son is 5 Correct Answer Incorrect Answer
    C Father is 30, son is 20 Correct Answer Incorrect Answer
    D Father is 35, son is 15 Correct Answer Incorrect Answer
    E Father is 38, son is 12 Correct Answer Incorrect Answer

    Solution

    Let the present age of the father be F and the present age of the son be S. According to the question: F + S = 50 (Equation 1). After 10 years, F + 10 = 4(S + 10) (Equation 2). Substitute Equation 1 into Equation 2: F = 50 - S. 50 - S + 10 = 4(S + 10). 60 - S = 4S + 40. 60 - 40 = 4S + S. 20 = 5S. S = 4. Substitute S = 4 into Equation 1: F + 4 = 50, F = 46. Father's age = 46 years, Son's age = 4 years. Correct answer: a. Father is 46, son is 4               

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