### Brain Teasers

# Alternating Series

Which TWO things come next in the following series:

31, E, 62, O, 58, T, 64, R, 8, T, 80, Y, 68, T...

31, E, 62, O, 58, T, 64, R, 8, T, 80, Y, 68, T...

### Hint

The numbers and letters change for different reasons.### Answer

The next two are 82 and O. The number sequence is:31 x 2 = 62

62 - 4 = 58

58 + 6 = 64

64 / 8 = 8

8 x 10 = 80

80 - 12 = 68

68 + 14 = 82

You can see that the number increases by two each time and repeats in the order of multiplying, subtracting, adding, and dividing.

Then the letter sequence is the last letter from the number before it:

Thirty-one - last letter E

Sixty-two - last letter O

Fifty-eight - last letter T

Sixty-four - last letter R

Eight - last letter T

Eighty - last letter Y

Sixty-eight - last letter T

Eight-two - last letter O

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