There are 267 students and 21 adults going on a school trip. An equal number of people will ride on each bus. If there are 9 buses, how many people will ride on each bus? Write and solve equations.

Step 1 ：Let \( s \) represent the number of students, \( a \) represent the number of adults, \( b \) represent the number of buses, \( t \) represent the total number of people, and \( p \) represent the number of people per bus.

Step 2 ：We are given \( s = 267 \), \( a = 21 \), and \( b = 9 \).

Step 3 ：First, we find the total number of people going on the trip by adding the number of students and adults: \( t = s + a \).

Step 4 ：Substitute the given values into the equation: \( t = 267 + 21 \).

Step 5 ：Simplify to find the total number of people: \( t = 288 \).

Step 6 ：Next, we divide the total number of people by the number of buses to find the number of people per bus: \( p = \frac{t}{b} \).

Step 7 ：Substitute the values into the equation: \( p = \frac{288}{9} \).

Step 8 ：Simplify to find the number of people per bus: \( p = 32 \).

Step 9 ：\(\boxed{32}\)