Question : Directions: Below are given some Roll Numbers of candidates registered at different centers for examination. The first two digits from the left stand for the center code and the next four for the serial number of the candidates registered at the center.

Now answer the following question based on this sample of Roll Numbers.
Which of the following centers had maximum serial numbers whose all digits are even?

Option 1: 83

Option 2: 56

Option 3: 65

Option 4: 85

Correct Answer: 83

Solution : There are 5 centers in total, namely –
83 (Highlight with red), 65 (Highlight with blue), 56 (Highlight with green), 85 (Highlight with pink), 48 (Highlight with purple)

The highlighted figure will be –

Let's check each option –
First option: 83 → 4381 / 6542 / 6989 / 2684 / 1264 / 6889 (There is 1 serial number with all even digits i.e. 2684)
Second option: 56 → 2068 / 7956 / 2639 / 1096 / 2109 (There is 1 serial number with all even digits i.e. 2068)
Third option: 65 → 3831 / 0183 / 7596 / 6899 / 2290 / 2920 (None of the serial number has all even digits)
Fourth option: 85 → 5493 / 4350 / 2096 / 4593 / 0960  (None of the serial number has all even digits)

As 2684 > 2068, so, 83 will be the answer. Hence, the first option is correct.