Question

At the start of summer vacation, Wesley decides to learn a number of kanji characters each week. The total number of characters Wesley knows, y, is a function of the number of weeks, I. The graph of the function passes through the points (3, 120) and (5, 160).
Find and describe the rate of change of the function.
The rate of change is
It represents the number of characters Wesley learns ?

Answer 1

Rate of change = (160 − 120) / (5 − 3) = 40 / 2 = 20.

It represents 20 characters per week — Wesley learns 20 additional kanji each week.