Letter sequence
Only one letter fits
A letter-sequence question that looks simple until you check the alphabet gaps.
Quick answer
Answer: U
The alphabet positions are 1, 3, 6, 10, and 15. The gaps are 2, 3, 4, and 5, so the next gap is 6. Fifteen plus 6 is 21, which is U.
How to use it
1
Turn each letter into its alphabet position.
2
Write the gaps between positions.
3
Notice the gaps climb by one.
4
Move 6 letters forward from O.
What this trains
Sequential reasoning
Alphabet mapping
Working memory
Rule extension
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