Five orchard baskets hold apples labeled with numbers following a strict pattern: 3, 7, 15, 31, and X. If each basket's apple count is one more than double the previous basket, how many apples are in basket X?
63 apples
The rule doubles the previous number and adds 1: (3*2)+1=7, (7*2)+1=15, (15*2)+1=31. For basket X: (31*2)+1 = 63.
About this riddle
Logic riddles give you a few facts and ask what must be true. List what you know, cross out what cannot be, and see what is left.
Difficulty: Medium. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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