Answer:
7 buses and 8 vans
Step-by-step explanation:
We know that 292 students went on a trip. Each van holds 9 students and each bus holds 30 students and total 15 vehicles were used.
Assuming the vans as [tex]v[/tex] and buses as [tex]b[/tex], we can make the following equations with the help of the given data:
[tex]v+b=15[/tex] --- (1)
[tex]9v+30b = 282[/tex] --- (2)
Using the substitution method:
[tex]v=15-b[/tex]
Putting this value of [tex]v[/tex] in equation 2:
[tex]9(15-b)+30b=282[/tex]
[tex]135-9b+30b=282[/tex]
[tex]21b=282-135[/tex]
[tex]21b=147[/tex]
[tex]b=7[/tex]
so [tex]v=15-7=8[/tex]
Therefore, 7 buses and 8 vans were used on the trip by the class.