Stephanie sells 12 pretzels per hour. Robert sells 15 pretzels per hour. This week, Robert sold an additional 18 pretzels. Which of the following expressions represents the total sales of both people this week, where S represents the number of hours that Stephanie worked and R represents the number of hours that Robert worked?

Question

A.
12
S
+
15
R
+
18

B.
15
S
+
12
R
+
18

C.
12
S
+
18
R

D.
12
S
+
15
R

Answer 1

To find the total sales of both Stephanie and Robert for the week, we can break down their sales as follows:

1. Stephanie's Sales: She sells 12 pretzels per hour, so if she worked for \( S \) hours, her total sales would be \( 12S \).

2. Robert's Sales: He sells 15 pretzels per hour. If he worked for \( R \) hours, his sales would be \( 15R \). However, we also know that this week, Robert sold an additional 18 pretzels, so we need to add that to his total.

Thus, Robert's total sales would be \( 15R + 18 \).

Combining both Stephanie's and Robert's total sales, we get:

Total Sales = Stephanie's Sales + Robert's Sales \[ = 12S + (15R + 18) \] \[ = 12S + 15R + 18 \]

From the options given, the correct expression that represents the total sales of both people this week is:

A. \( 12S + 15R + 18 \)