<PRE><B>Question 152483</B>
You have one equation in error.
People  51b + 8b = 193
Should be 
People  51b + 8s = 193

Now s+b=8
s = 8-b

51b + 8(8-b) = 193
64 + 43b = 193
43b = 129
b = 3
That makes s = 5

What is interesting in this problem is that you are not told to use all the drivers. So, we could use 4 buses and move them all. That saves 4 drivers to so something else. Assuming the cost for gas for one b is less than 4 SUVs, give the other 4 drivers something better to do.

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