Based on a survey of $200$ students, $140$ students like cold drinks, $120$ students like milkshakes, and $80$ students like both. How many students like at least one of the drinks?

Let $C$ be the set of students who like cold drinks and $M$ be the set of students who like milkshakes.
From the given data:

* Total number of students surveyed, $n(U)=200$
* Number of students who like cold drinks, $n(C)=140$
* Number of students who like milkshakes, $n(M)=120$
* Number of students who like both drinks, $n(C\cap M)=80$

We need to find the number of students who like at least one of the drinks, which is represented by $n(C\cup M)$.

Using the principle of inclusion-exclusion:

$$n(C\cup M)=n(C)+n(M)-n(C\cap M)$$

Substituting the values:

$$n(C\cup M)=140+120-80$$

$$n(C\cup M)=260-80=180$$

Thus, $180$ students like at least one of the drinks.