6. B
9. B
For number 6, 10 vans times 12 students is 120 students. 432 - 120 = 312. 312 students divided by 6 buses is 52. To check if it right I tried Middle School B. 5 vans times 12 students is 60. 164 students - 60 = 104. 104 divided by 2 buses equals 52. So 12 students is the right answer.
For number 9, 35*2=70 and 15*5=75. 70+75=145.
