Answer:
b = 48
v = 6
Step-by-step explanation:
Equations:
6v + 8b = 420students
12v + 11b = 600students
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Modify for elimination::
12v + 16b = 840
12v + 111b = 600
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Subtract and solve for "b"::
5b = 240
b = 48 (# of students in each bus)
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Solve for "v"::
6v + 8b = 420
6v + 8*48 = 420
6v = 420-384
6v=36
v = 6 (# of students in each van)
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For Check
12(6)+11(48)=600
72+528=600
600=600