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WE:Science (Other)
There are 20 cards in a box and each card is numbered from 1 to 20. Bi
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30 Jan 2021, 18:42
If you pull 1 then every even card in a row you'll get {1,2,4,6,8,10,12,14,16,18,20} then you'll need one more to get an even sum. That set is 11 integers, so I'd guess the answer is 12, because you'd have to pull one more card and it would be odd, since there are no evens left: hence 12 cards would be pulled and guarantee an even sum.
I venture to guess D.