CUET Preparation Today
The probability that out of 10 persons, all born in April, at least two have the same birthday is: |
$\frac{{^{30}C}_{10}}{(30)^{10}}$ $1-\frac{{^{30}C}_{10}}{30!}$ $\frac{(30)^{10}-{^{30}C}_{10}}{(30)^{10}}$ None of these |
None of these |
Total no. of ways to allot 30 days to 10 people = 3010 Allot 10 days to 10 people as birthday = 30C10 × 10! P(at least 2 have same birthday) = 1 - P (no one has same birthday) = $1-\frac{{^{30}C}_{10}×10!}{30^{10}}$ |
