Friends coming over to you for water puzzle
You have a large number of friends coming over and they all get thirsty. Your first friend asks for 1/2 a cup of water. Your second friend asks for 1/4 a cup of water. Your third friend asks for 1/8 a cup of water, etc.
How many cups of water do you need to serve your friends?
1 Cup.
Because 1/2+1/4+1/8+…….will add upto 1.This is a mathematical property
That is incorrect. It is 7/8 of a cup. 1/2 (=4/8) + 1/4 (=2/8) + 1/8 = 7/8. It’s the law of common denominators.
It doesn’t stop after the third friend. It continues on with the “large number of friends”. Doesn’t matter exactly how many friends because eventually the series converges to 1. So 1 cup is correct
3. You need a cup for each person.
You need 7/8 of a cup.
1st friend – 1/2 cup = 4/8
2nd friend – 1/4 cup = 2/8
3rd friend – 1/8 cup = 1/8
4/8 + 2/8 + 1/8 = 7/8
Your Answer
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