Answer: 100 miles
Explanation:
Hi to answer this question we have to write a system of equations.
To obtain the cost of company A (A) we have to add the fixed cost (100) and the product of the cost per mile (30) an the number of miles (d) .
A = 100+ 0.30d
Same for the cost of company B (B)
B= 70+ 0.60d
To find the number of miles in a day at which the rental costs for Company A and Company B are the same, both costs must be equal.
A =B
So
100+ 0.30d=70+ 0.60d
Solving for d
100-70 =0.60d-0.30d
30=0.30d
30/0.30=d
d= 100 miles