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 this week, we consider their individual pretzel sales and the additional pretzels Robert sold.

1. Stephanie's Sales: She sells 12 pretzels per hour. 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 total sales from selling pretzels would be \( 15R \). Additionally, he sold 18 extra pretzels this week, making his total sales \( 15R + 18 \).

Thus, the total sales of both Stephanie and Robert combined can be expressed as:

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

Therefore, the correct expression that represents the total sales of both people this week is:

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