Respuesta :
A) Let's call:
x = amount charged per day
y = amount charged per mile
According to Brynn you have: 5x + 200y = 240
According to Danielle: 2x + 100y = 100
You need to solve the system in order to find the amount charged:
[tex] \left \{ {{5x + 200y = 240} \atop {2x + 100y = 100}} \right. [/tex]
Solve for x on the second equation:
x = (100 - 100y) / 2 = 50 - 50y
Substitute in the first equation and solve for y:
5(50 - 50y) + 200y = 240
250 - 250y + 200y = 240
-50y = -10
y = 1 / 5 = 0.20
Now substitute this value in the equation found for x:
x = (50 - 50·0.20) = 40
Therefore the cost for Francesca will be:
C = 40·D + 0.20·M
The correct answer is B)
B) In order to find the cost for 250 miles and 4 days, you need to substitute the numbers in the formula found in part A):
C = 40·D + 0.20·M
= 40·4 + 0.20·250
= 210$
The cost estimated for Francesca is 210$.
x = amount charged per day
y = amount charged per mile
According to Brynn you have: 5x + 200y = 240
According to Danielle: 2x + 100y = 100
You need to solve the system in order to find the amount charged:
[tex] \left \{ {{5x + 200y = 240} \atop {2x + 100y = 100}} \right. [/tex]
Solve for x on the second equation:
x = (100 - 100y) / 2 = 50 - 50y
Substitute in the first equation and solve for y:
5(50 - 50y) + 200y = 240
250 - 250y + 200y = 240
-50y = -10
y = 1 / 5 = 0.20
Now substitute this value in the equation found for x:
x = (50 - 50·0.20) = 40
Therefore the cost for Francesca will be:
C = 40·D + 0.20·M
The correct answer is B)
B) In order to find the cost for 250 miles and 4 days, you need to substitute the numbers in the formula found in part A):
C = 40·D + 0.20·M
= 40·4 + 0.20·250
= 210$
The cost estimated for Francesca is 210$.