Eight unmarked envelopes contain the numbers: 1, 2, 4, 8, 16, 32, 64, 128. Eve chooses a few envelopes randomly. Alie takes the rest. Both sum up their numbers. Eve's sum is 31 more than Alie's. How many envelopes did Eve take?
Select one option, then click Submit.
2
3
4
5
6
Select an option, then submit.
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Pink Kangaroo 2016 (2016)
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