The amount of money Joaquin took out of his bank account in January is shown on the vertical number line below.

Question

A point is 20 units below 0.

Joaquin then added $65.71 to his account in February. What was the overall change in Joaquin’s bank account for January and February combined?

A.
−
$
85
.
71

B.
−
$
45
.
71

C.
$
45
.
71

D.
$
85
.
71

Answer 1

To find the overall change in Joaquin's bank account for January and February combined, we start by determining the amount he took out in January.

Since the point is 20 units below 0, that means Joaquin withdrew \( -20 \) (or \( -20 \) dollars).

In February, he added $65.71 to his account, which is a positive change.

Now we can combine the changes from January and February:

1. January: \( -20 \)
2. February: \( +65.71 \)

To find the overall change:

\[ -20 + 65.71 = 65.71 - 20 = 45.71 \]

So, the overall change in Joaquin's bank account for January and February combined is \( +45.71 \).

Thus, the answer is:

C. \( $45.71 \)