Question

    The average of five consecutive odd numbers is 45. What

    is the average of the first three numbers among them?
    A 43 Correct Answer Incorrect Answer
    B 40 Correct Answer Incorrect Answer
    C 45 Correct Answer Incorrect Answer
    D 55 Correct Answer Incorrect Answer
    E None of these Correct Answer Incorrect Answer

    Solution

    ATQ, Let the first number be 'y'. So, the numbers are y, (y + 2), (y + 4), (y + 6), (y + 8). ATQ: y + y + 2 + y + 4 + y + 6 + y + 8 = 45 × 5 Or, 5y + 20 = 225 Or, 5y = 205 Or, y = 205 / 5 = 41 So, the first three numbers are 41, 43, and 45. Required average = (41 + 43 + 45) / 3 = 129 / 3 = 43. Alternative solution: If the average of five consecutive odd numbers is 45, then the third number is 45 (since the average is equal to the middle term). So, the 2nd and 1st numbers are 43 and 41, respectively. So, the average of 41, 43, and 45 is 43 as the three numbers are also consecutive odd.

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