If the sum of two numbers is considered as 'a' and their product is considered…

2025

If the sum of two numbers is considered as 'a' and their product is considered as 'b', then what will be the sum of their reciprocals?

  1. A.

    a/b

  2. B.

    1/b + 1/b

  3. C.

    b/a

  4. D.

    ab

Attempted by 32 students.

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Correct answer: A

Step-by-Step Solution

To find the sum of the reciprocals of two numbers when their sum and product are known, we can derive the relationship algebraically.

  1. Define the variables:

    • Let the two numbers be P and Q.

    • According to the problem:

      • Sum of the numbers: P + Q = a

      • Product of the numbers: P * Q = b

  2. Express the sum of reciprocals:

    • The sum of their reciprocals is (1/P) + (1/Q).

    • To add these fractions, find a common denominator, which is P * Q.

    • (1/P) + (1/Q) = (Q / PQ) + (P / PQ)

    • This simplifies to: (P + Q) / (P * Q)

  3. Substitute the known values:

    • Replace (P + Q) with 'a' and (P * Q) with 'b'.

    • The expression becomes: a / b

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