Multiple choice

Which of the following is the least number that leaves a remainder value of “2” in each of the cases when divided by 28, 21 and 24?

  1. 180

  2. 280

  3. 170

  4. 150
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

L.C.M of 28, 21 and 24 = 2 x 2 x 2 x 7 x 3 = 168 Hence, the required number will be 168 + 2 = 170

AI explanation

A number that leaves the same remainder for several divisors can be found by first finding the LCM of the divisors and then adding that remainder. The LCM of 28, 21, and 24 is 168 (since 28=2²×7, 21=3×7, 24=2³×3, so LCM=2³×3×7=168). Adding the remainder of 2 gives 170, the least such number.

Keep practicing — related questions