I'm posting one puzzle, riddle, math, or statistical problem a day. Try to answer each one and post your answers in the comments section. I'll post the answer the next day. Even if you have the same answer as someone else, feel free to put up your answer, too!
Friday, October 30, 2009
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315
ReplyDeleteThe differences between the numbers are: 2240, 3360, 2520, and 210. That doesn't follow any discernable pattern, unless you look at the ratio of the differences to the original number:
2240 / 8960 = .25
3360 / 6720 = .5
2520 / 3360 = .75
210 / 840 = .25
So, we have a repeating sequence in the ratios { .25, .5, .75 }. The next in the sequence is .5, , meaning the next number will be half the current number, hence 315.
8960 * 0.75 = 6720
ReplyDelete6720 * 0.5 = 3360
3360 * 0.25 = 840
again...
840 * 0.75 = 630
630 * 0.5 = 315
315 * 0.25 = 78.75 ......
so the seq would be
8960, 3360, 840, 630, 315, 78.75, ......
As always, you impress me with how you get these. The answer, as already pointed out by harryc and sadeesh is 315.
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