Question

The owner of a bookstore recorded the following information from last

week:
12
18
24
30
36
42
Number of
Customers,
С
Amount of
Sales,
S
$80
$110
$140
$170
$200
$230
According to this information, which equation describes the relationship
between the number of customers and the amount of sales?
A. S = 50 + 20
C. s = 6c + 20
B. s = c + 30
D. s = 6c + 8

Answer 1

s=5c+20

Explanation:

hope this helps

Answer 2

The equation that describes the relationship between the number of customers and the amount of sales is S = 5C + 20.

How the equation of the relationship was derived.

Let's denote number of customers with C and the number of amount of sales with S.

The relationship between the number of customers C and the amount of sales S can be derived as follows.

The rate of change (slop) = Change in S/Change in C

Take two points

let's use points (12,80) and (36,200)

Change in S = 200-80

= 120

Change in C = 36-12

= 24

Slope = 120/24

= 5

Equation of line is given as

y = mx + b

S = 5C + b

Find b by substituting (12,80) into the equation

80 = 5(12) + b

80 = 60 + b

b = 20

S = 5C + 20

Therefore, the equation that describes the relationship between the number of customers and the amount of sales is S = 5C + 20.