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?**

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.

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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