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    (x, y) is a pair of positive integers such that HCF (x, y) + LCM (x, y) = 187 and x > y.Which one of the following is correct in respect of the Que
    Question

    (x, y) is a pair of positive integers such that HCF (x, y) + LCM (x, y) = 187 and x > y.

    Which one of the following is correct in respect of the Question and the Statements given below?

    Statement 1: There are three possible values of HCF (x, y).

    Statement 2: The minimum value of (x + y) is 37.

    Statement 3: There are 7 pairs of (x, y) that satisfy the given conditions.

    A.

    Statements 1 and 3 are correct but Statement 2 is incorrect.

    B.

    Statement 1 is incorrect but Statements 2 and 3 are correct.

    C.

    Only Statements 1 and 2 are correct.

    D.

    All three statements are correct.

    Correct option is D

    Given:
    (x, y) is a pair of positive integers
    HCF of x and y plus LCM of x and y is equal to 187
    Also, x is greater than y
    We are given three statements:
    There are three possible values of HCF(x, y)
    The minimum value of (x + y) is 37
    There are 7 such (x, y) pairs that satisfy the condition
    We are to evaluate which of the statements are correct.
    Concept:
    Let:
    HCF of x and y = h
    Then x = h × m, y = h × n
    Where m and n are coprime integers, and since x > y, m > n
    The LCM of x and y will be:
    LCM = (x × y) / HCF = (h × m × h × n) / h = h × m × n
    Now, the equation becomes:
    HCF + LCM = h + h × m × n = h × (1 + m × n)
    We are given:
    h × (1 + m × n) = 187
    This equation is key. We’ll now use it to find valid h values and count the valid (m, n) pairs for each.

    Solution:
    Step 1: Factor 187
    187 = 11 × 17
    Factors of 187: 1, 11, 17, 187

    Try each factor of 187 as a possible value of h.

    Step 2: Try h = 1
    Then 1 + m × n = 187 → m × n = 186

    Now, find all coprime pairs (m, n) such that:

    m × n = 186

    m > n

    HCF(m, n) = 1

    Factor pairs of 186:

    (186, 1), (93, 2), (62, 3), (31, 6)

    Check which of these are coprime:

    (186, 1): coprime

    (93, 2): coprime

    (62, 3): coprime

    (31, 6): coprime

    Total valid pairs for h = 1: 4

    Step 3: Try h = 11
    Then 1 + m × n = 187 / 11 = 17
    → m × n = 16

    Factor pairs of 16:

    (16, 1), (8, 2), (4, 4)

    Check for coprimality:

    (16, 1): coprime

    (8, 2): not coprime

    (4, 4): not coprime

    Total valid pairs for h = 11: 1

    Step 4: Try h = 17
    Then 1 + m × n = 187 / 17 = 11
    → m × n = 10

    Factor pairs of 10:

    (10, 1), (5, 2)

    Both pairs are coprime.

    Total valid pairs for h = 17: 2

    Step 5: Try h = 187
    Then 1 + m × n = 187 / 187 = 1
    → m × n = 0 — Invalid

    Final Count:
    h = 1 → 4 valid pairs

    h = 11 → 1 valid pair

    h = 17 → 2 valid pairs
    Total = 4 + 1 + 2 = 7 valid pairs

    Check Each Statement:

    Statement 1: There are three possible values of HCF(x, y)
    Correct — we found valid values of h as 1, 11, and 17
    So Statement 1 is correct

    Statement 2: The minimum value of x + y is 37
    Try the pair (31, 6), from h = 1 and (m, n) = (31, 6)

    x = 1 × 31 = 31

    y = 1 × 6 = 6

    x + y = 37

    This is the minimum among all valid pairs, so
    Statement 2 is correct

    Statement 3: There are 7 valid pairs (x, y)
    We found exactly 7 valid coprime (m, n) pairs, hence 7 valid (x, y) pairs
    So Statement 3 is correct

    Final Answer: D — All three statements are correct

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