Solution (Part-A)
Note that:
- Given clue: A class must have fewer than 18 students
Let's reread the clue carefully.
{A class} must have {fewer} than {18 students}
↥ ↥ ↥
n < 18
The inequality formed: n < 18
This means that the solution of the inequality can be anything except 18 or above 18.
Solution (Part-B)
Note that:
- Given clue: The class must have at least 15 students
Let's reread the clue carefully.
{The class} must have {at least} {15 students}
n ≥ 15
The inequality formed: n ≥ 15
This means that the solution of the inequality can be 15 or less than 15.
Solution (Part-C)
The value of n that can be a solution of both inequalities can be 15, 16, and 17.
Hoped this helped!