Question

Catherine found that as she increase the price of a chocolate bar the numbers of sales per week decreased

Week1 149
Week2 143
Week3 137
Week4 131
Week5 125

A. write a formula for the arithmetic sequence that represents the number of sales per work.

B. Explain how you could use the information to predict the number of sales for the eighth week

Answer 1

A. f(x)=155-6x

B. Plug in x=8 and solve.

Explanation:

-we can develop an equation for this by first realizing that each week, the sales decrease by 6. thus, we know the amount of sales decreases by 6 every week so we know the formula is: the initial sales amount-6x (x being whatever week).

-we can find the initial amount by noting i=initial sales amount and using the Info from the first week.

149=i-6(1)

155=I

thus, the formula: f(x)=155-6x

- we can plug in 8=x to predict the sales amount on the eighth week:

155-6(8)

155-48

sales on eighth week=107