C3_W1_Lab 1_Four Birthday Problems

In problem 1,
the solution to number of people needed such that probability of 2 people having same birthday comes out to be 254.

But in class the way it was solved it came out as 23.
What am I understanding incorrectly here?

Kindly verify this. :face_with_peeking_eye:

Okay I think what I misunderstood is:

In the class-

We found that if we have 23 people then there is >50% chance that atleast 2 people have same birthday.
We tried finding probability that NO ONE has same birthday among themselves.

In lab problem 1-

The situation of interest is that NO ONE has birthday as that of one specific student. BUT there may be 2 people who have same birthday (just not same as the one specific student).
Ex. If bday of specific student is 1 March then no other student has birthday on 1 March BUT there maybe 2 students who have birthday of (say) 1 Jan.

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