Answer:
See explanation
Explanation:
1. 400 students in total.
Category 1: Students which rode the bus (180)
Category 2: Students that were freshmen (115)
Let x be the number of students in both categories. Then
- 180 - x students rode the bus and were not freshmen
- 115 - x students were freshmen and didn't ride the bus
So, 115 - x = 25
x = 90
Thus,
- 90 students rode the bus and were freshmen
- 90 students rode the bus and were not freshmen
- 25 students were freshmen that did not ride the bus
- 400 - 90 - 90 - 25 = 195 students didn't rode the bus and were not freshmen
2. 350 students in total.
Category 1: Students bought pizza (168)
Category 2: Students that were sophomores (123)
Let x be the number of students in both categories. Then
- 168 - x students that bought pizza and were not sophomores
- 123 - x students were sophomores and didn't buy pizza
So, 123 - x = 32
x = 91
Thus,
- 91 students bought pizza and were sophomores
- 77 students bought pizza and were not sophomores
- 32 students were sophomores that did not buy pizza
- 350 - 91 - 77 - 32 = 150 students didn't buy pizza and were not sophomores