I hesitated to add this because it’s poorly worded, ambiguous and the answer could be almost anything. I prefer teasers with a single answer, but there you go.
If you came up with a different answer and can explain how you did it, don’t think you’re wrong. It’s probably just as valid. Feel free to share yours in the comments.
My answer for the first number is 2.
Here’s how I got it.
The generic rule for a number in the sequence is: 2^(n – 1) + 1, where n is the position in the sequence.
Note: The teaser doesn’t specify the position of 17. In this case, it’s fifth.
Position 1: (so n = 1) is 2^(1 – 1) + 1 = 2
Position 2: 2^(2 – 1) + 1 = 3
Position 3: 2^(3 – 1) + 1 = 5
Position 4: 2^(4 – 1) + 1 = 9
Position 5: 2^(5 – 1) + 1 = 17
For the curious, the next 5 numbers of the sequence would be:
Jim was canoeing on a lake when a sudden thunderstorm blew in tipped his boat. He swam to a rocky island about a mile from his family’s cottage and found a small, abandoned shack. Inside was an old kerosene lamp and a few matches. All the wood on the island was too damp to burn and the lamp was his only means of signaling for help but it only held an inch of kerosene, not enough to reach its short wick. How did he get the lamp burning to summon help?
Knowing kerosene and water wouldn’t mix and kerosene is less dense than water, he dipped the lamp in the lake and filled it with enough water so the kerosene rose to the top to cover the wick. The lamp was still burning an hour later when a motorboat rescued him.
Brandon was walking around at the carnival. A man called out from a booth and said, “If I can write your exact weight on this piece of paper, you have to pay me $50. If I can’t do it, I’ll pay you $50.”
Brandon checked the booth for a scale but saw nothing. He agreed. Since your weight can fluctuate by a pound or two, he decided that no matter what number the man wrote, he would just say he weighed a pound more or less. In the end, the man in the booth won the $50. How did he do it?