Answer: The answer is 3 buses.
Step-by-step explanation: Given that the students are going on a field trip, where
number of third graders = 28,
number of fourth graders = 76
and
number of fifth graders = 46.
Therefore, the total number of students who are going on the field trip
= 28+76+46 = 150.
Since a bus can hold 50 students, so the number of buses 'n' required for the trip is given by

Thus, 3 buses are necessary to transport all the students.