Answer:
(A) 30x+90=300
(B) $7
Explanation:
Let x be the roller skating rink's entrance fee for one student.
So, the entrance fee for 30 students=30x
As each student pays a $3 fee to rent skates
So, the fee for rent paid by 30 students= $3x30=$90
The total cost for the students to enter the rink and rent skates= 30x+90
As given that total fee to enter the rink and rent skates is $300.
Therefore, 30x+90=300
(A) The required equation is 30x+90=300.
(B) On solving the equation, we have

Hence, the roller skating rink's entrance fee is $7.