What is the missing number 2,4,8,7,5,10,11?

The next number is 13. Here are the differences between the even and odd numbers: Odd: +6, -3, +6. Even: +3, +3, +3. 11 is an odd number of the sequence, so we have to find the even number. Since even increases by 3 each time, do 10 (the last even number) +3. After 13 is 8, then 16, 14, 19, 11, 22, 17, etc. read more

I assume that the number which is divisible by 3 is removed from the series. 2,3,4,5,6,7,8,9,10,11,12,13, n. And arranged in random order. So answer is 13. Which is not divisible by 3. read more

In this alternating repetition series, the random number 21 is interpolated every other number into an otherwise simple addition series that increases by 2, beginning with the number 9. read more

How to find a missing number in a sequence. Determine if the order of numbers is ascending (getting larger in value) or descending (becoming smaller in value). read more