Question

Mia opens a savings account with $100. She makes the same deposit every month and makes no withdrawals. After 2 months, she has $150. After 4 months, she has $200. After 6 months, she has $250. What is the rate of change?

Answer 1

We have been given that Mia opens a savings account with $100. She makes the same deposit every month and makes no withdrawals. After 2 months, she has $150. After 4 months, she has $200. After 6 months, she has $250.

We are asked to find the rate of change.

The rate of change will be equal to slope. We have been given points (2,150), (4,200) and (6,250). We will use slope formula to find rate of change.

$m=\frac{y_2-y_1}{x_2-x_1}$

Let $(2,150)=(x_1,y_1)$ and $(4,200)=(x_2,y_2)$.

Upon substituting coordinates of these points in slope formula, we will get:

$m=\frac{200-150}{4-2}$

$m=\frac{50}{2}$

$m=25$

Therefore, the rate of change is $25 per month.