Question

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

Answer 1

the dreaded riddles are back!

Answer 2

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

Answer 3

so @hartnn do you know the answer?

Answer 4

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

Answer 5

helping huh. haven't tried that in a while

Answer 6

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)

Answer 7

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

Answer 8

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

Answer 9

ooooh so close

Answer 10

but no

Answer 11

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