Answer:

Step-by-step explanation:
I suggest looking lessons on it online if you don't understand... It's hard to do your work especially if you don't understand it. Or if your online, go to past lessons or something.
Answer:450
Step-by-step explanation: If you add 150 to 150 that will give you 300.If you add 300 to 100 that will give you 400.Finally if you add 400 to 50 that will give you 450.
Your answer is: 450 students
0.88. you can simply see this by using the right use of the data