## anonymous 3 years ago LEGEN...waitforit...DARIDDLE: How many people should be in a room so that there is a 99% probability that two or more people share the same birthday? Hint: whoever gets it right with solutions gets a medal

1. hartnn

2. anonymous

these ones are legendary. i don't make puny riddles like the original

3. anonymous

so @hartnn do you know the answer?

4. hartnn

haven't tried yet...i would always prefer helping than satisfying my own thirst of solving puzzles...i'll try that in free time :)

5. anonymous

helping huh. haven't tried that in a while

6. hartnn

i try these problems by taking small numbers first let there be just 2 people in that room then the probability "that two or more people share the same birthday" will be 1- probability that BOTH will not have same birthday (assuming 366 days a year) so, $$\large 1- \dfrac{366}{366}\times \dfrac{365}{366}$$ now extending this for 'n' people $$\large 0.99 =1- \dfrac{\dfrac{366!}{(366-n)!}}{366^n}$$ am i on right path ? (wondering how the hell can i solve that for n :O O.o)

7. anonymous

lol. am not saying if you're on the right path or not. just tell me the answer and i'll tell you if it's right. that's how riddles work

8. hartnn

rounding to nearest integer i am getting 55 people (infact 55 or more!)

9. anonymous

ooooh so close

10. anonymous

but no

11. hartnn

i had my chance, i'll let others try....