X is the first mile and y are the additional miles
So, 1*x + y * 9 (9 because we have the additional miles less the first mile X 10 - 1 = 9 )
1)x + 9y = 0.90 + 8y ( we can't solve) INSUFF
2) x + 9y = 1.20 + 6y INSUFF
1) + 2) we can subsistute and solve
C should be the answer
The answer is correct, it is C.
Just something to consider: when you are already given the variables - f
the prices in cents for the first mile and the additional miles, respectively, no need to define new variables, just to have the prices in dollars.
And I wouldn't suggest just picking automatically the x
variables when dealing with some quantities with some specific meaning. f
irst and m
iles are suggestive.
your two equations would be:f+9m=90+8m f+9m=120+6m
PhD in Applied Mathematics
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