best rentals charges a daily fee plus a mileage fee for renting its cars. barney was charged $159 for 3 days and 300 miles, while mary was charged $289 for 5 days and 600 miles. what does best rental charge per day and per mile?

Respuesta :

Answer:

Let charge per day be $x  and charge per mile be $y  

then:

as per the given condition we have;

3x + 300y =159          .....[1]

5x + 600y = 289       .....[2]

Multiply equation [1] both sides by 5 we get;

[tex]5(3x+300y) = 5 \cdot 159[/tex]

Using distributive property: [tex]a \cdot(b+c) = a\cdot b+ a\cdot c[/tex]

15x+1500y = 795                 .....[3]

Multiply equation [2] by 3 both sides we get;

[tex]3(5x+600y) = 3 \cdot 289[/tex]

Using distributive property: [tex]a \cdot(b+c) = a\cdot b+ a\cdot c[/tex]

15x+1800y = 867                    .....[4]

Subtract equation [3] from [4] to eliminate x and solve for y;

15x+1800y-15x-1500y = 867 -795

Combined like terms;

300y = 72

Divide both sides by 300 we get;

[tex]y = \frac{72}{300}=0.24[/tex]

⇒  y =$0.24 per mile.

Now substitute this value y in equation [1] to solve for x;

3x + 300(0.24) =159

3x + 72 =159

Subtract 72 both sides we get;

3x + 72 -72 = 159 -72

Simplify:

3x = 87

Divide both sides by 3 we get;

[tex]x = \frac{87}{3} = 29[/tex]

Therefore, the best rental charges per day is, $ 29 and the charges per mile is, $0.24