In a division sum, the remainder was 71. With the same divisor but twice the…

2023

In a division sum, the remainder was 71. With the same divisor but twice the dividend, the remainder is 43. Which one of the following is the divisor ?

  1. A.

    123

  2. B.

    101

  3. C.

    99

  4. D.

    345

Show answer & explanation

Correct answer: C

Step-by-Step Solution

The division algorithm states that Dividend = (Divisor × Quotient) + Remainder. Let's use this to solve the problem.

  1. Set up the first scenario:

    • Let the divisor be D.

    • Let the quotient be Q1.

    • Dividend = N = (D × Q1) + 71.

  2. Set up the second scenario:

    • When the dividend is doubled (2N), the divisor (D) remains the same.

    • Let the new quotient be Q2.

    • 2N = (D × Q2) + 43.

  3. Substitute the first equation into the second:

    • 2 × (D × Q1 + 71) = D × Q2 + 43

    • (2 × D × Q1) + 142 = (D × Q2) + 43

    • 142 - 43 = (D × Q2) - (2 × D × Q1)

    • 99 = D × (Q2 - 2 × Q1)

  4. Interpret the result:

    • This equation shows that 99 must be a multiple of the divisor D. Since 99 is the result of the division process modification, the divisor D is 99.

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