Number System Questions

Multiple choice
  1. 666

  2. 676

  3. 682

  4. 728

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The 2-digit numbers giving a remainder of 3 when divided by 7 are of the form 7n + 3. The smallest such number is 10 (n=1) and the largest is 94 (n=13). This forms an arithmetic progression: 10, 17, ..., 94, with 13 terms. The sum is (n/2) * (first + last) = (13/2) * (10 + 94) = (13/2) * 104 = 13 * 52 = 676.