Question

    Calculate the number of factors of 480.

    A 20 Correct Answer Incorrect Answer
    B 18 Correct Answer Incorrect Answer
    C 36 Correct Answer Incorrect Answer
    D 24 Correct Answer Incorrect Answer

    Solution

    If prime factorization of a number 'N' = a p  X b q  X c r , then number of factors of 'N' are product of (p + 1) , (q + 1) and (r + 1) together.

    480 = 2 x 2 x 2 x 2 x 2 x 3 x 5 = 2 5  x 3 1  x 5 1

    So, total number of factors = (5 + 1) x (1 + 1) x (1 + 1) = 6 x 2 x 2 = 24

    Practice Next

    Relevant for Exams: