Ms. Martina filled her truck's gas tank with
28.7 gallons of gas. If she drove 100 miles
on the same tank of gas, how much gas did
she use per mile?

i think the answer is 0.287

Step-by-step explanation:

i divided 28.7/100 which gave me 0.287

a.)the line for function b is steeper

let x and 400 - x be the two numbers.  

==> 0.80x + 0.85(400 - x) = 400 - 68 from the statement of the problem.  

< ==> 0.80x + 0.85(400 - x) = 400 - 68  

==> 340 - 0.05x = 332  

< ==> -0.05x = -8 ==> x = 160, the first number ==> 400 - x = 240, the second number.