The number of miles in a day at which the rental costs for Company A and Company B are the same is 200 miles.
Explanation:
Let the number of miles be m
Rent from Company A = $80 + m X $0.2
Rent from Company B = $60 + m X $0.3
Rental costs of both company A and B are same
So,
$80 + m X $0.2 = $60 + m X $0.3
$80 + $0.2m = $60 + $0.3m
$80 - $60 = $0.1m
$20 = $0.1m
m = 200
Therefore, number of miles in a day at which the rental costs for Company A and Company B are the same is 200 miles.