Question

    R goes to the gym either by cycle, car, or walking. On a specific day, the probability of him going by car is 0.3 less than the probability of walking and 0.14 more than the probability of cycling. What is the probability that he went to the gym by either car or cycle on that day?

    A (23/50) Correct Answer Incorrect Answer
    B (21/50) Correct Answer Incorrect Answer
    C (21/40) Correct Answer Incorrect Answer
    D (27/55) Correct Answer Incorrect Answer
    E none of these Correct Answer Incorrect Answer

    Solution

    ATQ, Let the probability that he travelled by car = ‘c’ Then, probability that he travelled by cycling = (c – 0.14) Probability that he travelled by Walking = (c + 0.3) So, we have, c + (c – 0.14) + (c + 0.3) = 1 Or, 3c + 0.16 = 1 So, c = (1 – 0.16) ÷ 3 = 0.28 So, probability that R travelled by either car or Cycling = c + (c – 0.14)  = 0.28 + 0.14 = 0.42 = (21/50)

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