Question

A sandwich costs $0.75 more than a container of milk. A customer buys 4 sandwiches and 4 containers of milk. The customer pays $7.00. What is the cost of a sandwich?

Answer 1

Let x be the cost of a sandwich

7 = 4x + 4 (x-0.75)
7 = 4x + 4x - 3
10 = 8x
8x = 10
x = 10/8
x = 1.25
A sandwich is $1.25

Answer 2

Answer : The cost of sandwich is, $1.25

Step-by-step explanation :

Let the cost of sandwich be 'x' and the cost of container of milk be, 'y'

A sandwich costs $0.75 more than a container of milk. The equation will be:

$x=0.75+y$       .............(1)

A customer buys 4 sandwiches and 4 containers of milk. The customer pays $7.00. The equation will be:

$4x+4y=7.00$     ..............(2)

Now substitute the value of 'x' from equation 1 to equation 2, we get the value  of 'y'.

$4x+4y=7.00$

$4(0.75+y)+4y=7.00$

$3+4y+4y=7.00$

$3+8y=7.00$

$8y=7.00-3$

$8y=4.00$

$y=\frac{4.00}{8}$

$y=0.5$

Now put the value of 'y' in equation 1, we get the value of 'x'.

$x=0.75+y$

$x=0.75+0.5$

$x=1.25$

The cost of sandwich = x = $1.25

The cost of container of milk = y = $0.5

Thus, the cost of sandwich is, $1.25