What number comes next in the series: 5, 11, 23, 47, ...?
Category: Math · Difficulty: hard
Hint: Look at how each number is generated from the previous one.
Answer
91
Explanation
The pattern doubles the previous number and adds one: 5*2+1=11, 11*2+1=23, etc. Thus, 47*2+1=95.
This is a hard math riddle — a tricky one that takes a little thought. The answer is 91.
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