The graph shows Olivia’s total savings over seven weeks. Did her total savings decrease from week three to week seven?
To answer this question, we need to compare the amount of savings Olivia had in week three and week seven. Let’s look first at the amount of savings Olivia had in week three. We’ve located week three on the 𝑥-axis. Now, we need to draw a line across from the point to the 𝑦-axis, which will tell us how much money she’d saved.
A line meets the 𝑦-axis halfway between 60 and 80, which means that in week three she had saved 70 dollars. Now, let’s see how much she’d saved in week seven. So we draw a line up to the point from the 𝑥-axis and across from this point to the 𝑦-axis, where we can see that the line meets between 140 and 160. The number which is halfway between 140 and 160 is 150.
So in week three, Olivia had 70 dollars and in week seven she had 150 dollars. The question asks us if Olivia savings decreased from week three to week seven. But they didn’t. They increased from 70 dollars to 150 dollars.
So the answer to this question is no. Olivia savings did not decrease from week three to week seven. In fact, they increased.