1 of 8 0-day streak

Investigating systematic changes in formulas

Question 1 of 8

Calculator allowed

A fictional kit-order rule gives total cost C in dollars for quantity n, unit price p dollars per kit and one fixed fee f dollars

C=pn+f

All listed quantities are whole numbers of kits; the fee is added once, not once per kit

Only f varies. Keep n = 3 and p = 2 fixed throughout this table

(a)4 marks

Complete every cost in the table before comparing the settings

n	p ($)	f ($)	C ($)
3	2	6	?
3	2	7	?
3	2	8	?
3	2	9	?

Cost for n = 3, p = 2, f = 6 Cost for n = 3, p = 2, f = 7 Cost for n = 3, p = 2, f = 8 Cost for n = 3, p = 2, f = 9

(b)1 mark

Find the change in total cost between the first two rows. This is the change for each equal f-step in this table

Signed change in cost (dollars)