The number of miles she drove the van for is 250 miles
From the question, we are to determine the number of miles Shelly drove the van
The given equation which shows the relationship between the number of days she rented the van, d, and the number of miles she drove the van, m is
20d + 0.7m = 235
Now, if she rented the van for 3 days, that is, d = 3
Putting the value of d = 3 into the equation to determine the value of m
We get
20(3) + 0.7m = 235
60 + 0.7m = 235
0.7m = 235 - 60
0.7m = 175
m = 175 / 0.7
m = 250
Hence, the number of miles she drove the van for is 250 miles
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