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Proof that .99 repeating = 1?
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timmy_i_chen (952)

Can anyone help me find a proof that says .999 repeating is equal (no approximations) to 1? We got into a big discussion about this on Discord recently.

Answered by pyelias (680) [earned 5 cycles]
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pyelias (680)
.999999..
= 0.9 + 0.09 + 0.009 + ...
= 0.9 * (1 + 0.1 + 0.01 + 0.001 + ...)
= 0.9 * 1 / (1 - 0.1)
= 0.9 * 1 / 0.9
= 1
Gamerafa73 (3)

1/3 * 3 = 3/3 = 1
1/3 = 1 / 3 = 0,333333...

HarperframeInc (232)

Is this a test of a cool new feature??? @timmy_i_chen