Question

1, 2 ,3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 14, 15, 16, 18, 19, 20, The missing number is?​

Answer 1

Answer: 13

Explanation:

Here we have all of the numbers from 1 to 20. However, one of them is missing.

Given numbers:

1, 2 ,3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 14, 15, 16, 18, 19, 20

As we can see, 13 was skipped. If we include it back in, we'll get:

1, 2 ,3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 18, 19, 20