Three or more people having the same birthday. i am trying to determine the probability of three people having the same birthday when chosen from a group of "n" people. i have calculated that in a group of 23 people, the probability is greater than 50 per cent that at least 2 of those people will have the same birthday (and the calculations are here: ) i know the number of people required is 88 for 3 people, 187 for 4, 313 for 5, etc. (the link for that information is ~fcale/ccc/dc. pdf) anyway, when i use the attached formula, it becomes inaccurate when the number of people required is 6 or greater. does anyone know if there is a better equation (or method) to use when calculating this?

for a it would be 24 children.

for b i don't understand the question. is it saying for each individual person they pick 5 reds to 7 greens or is it the whole group. clarify and i hope this can you.

step-by-step explanation:

fabric (square meters)                   cloaks

7                                                           21

4/3                                                         4

step-by-step explanation:

we are told that harry needs 2 square meters of fabric for every 6 wizard cloaks he makes.

1. first of all we will find how many cloaks can be made from 1 square meter of fabric by dividing 6 by 2.

we can see that 3 cloaks can be made from 1 square meter of fabric. now we will multiply 3 by 7 to find number of cloaks made from 7 square meters of fabric.

therefore, harry will make 21 cloaks from 7 square meters of fabric.

2. let us find how many square meters of fabric will be needed to make 4 cloaks.

first of all we will find fabric needed for 1 cloak by dividing 2 by 6.

we can see that fabric needed for 1 cloak is   square meter. now we will multiply   by 4 to find fabric needed for 4 cloaks.