Brain Teasers
1, 4, 2, 8, 5, ?
What is the last number in this series?
1, 4, 2, 8, 5, ?
1, 4, 2, 8, 5, ?
Answer
7.They form a period of the decimal fraction 1/7, and the number 142857 has many interesting properties.
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Comments
Neat. But I don't think I've ever heard anything about that fraction before.
I have. Many Integers that form the reccuring part of a fraction (a reccuring fraction by the way is any fraction that has prime factors other than 2 and 5) also have interesting proporties.
Being that I've memorized the repeating digits of fractions 1/2 to 1/20, this one was easy for me.
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