Let's break down the problem step-by-step to determine the correct equation for Mark's earnings in a day, given the following information:
1. Fixed hourly income: Mark earns [tex]$\$[/tex]18[tex]$ per hour.
2. Sales commission: Mark earns a \(5\%\) commission on his sales.
To find Mark's total daily earnings \(y\), we need to consider both the fixed income he earns from working \(h\) hours and the commission he earns from making \(s\) dollars in sales.
### Step-by-Step Breakdown:
1. Fixed Income Calculation:
- Mark earns \( \$[/tex]18 \) per hour.
- If Mark works [tex]\( h \)[/tex] hours, his total fixed income for the day is [tex]\( 18h \)[/tex] dollars.
2. Commission Calculation:
- Mark earns a [tex]\( 5\% \)[/tex] commission on his sales.
- To express [tex]\( 5\% \)[/tex] as a decimal, we use [tex]\( 0.05 \)[/tex].
- If Mark's total sales amount to [tex]\( s \)[/tex] dollars, the commission he earns is [tex]\( 0.05s \)[/tex] dollars.
### Combining Fixed Income and Commission:
To get the total earnings [tex]\( y \)[/tex], we simply add the fixed income and the commission:
[tex]\[ y = 18h + 0.05s \][/tex]
Therefore, the correct equation that represents Mark's earnings in a day is:
[tex]\[ y = 18h + 0.05s \][/tex]
### Conclusion:
Given the choices provided:
- A. [tex]\( y = 18h + 0.5s \)[/tex]
- B. [tex]\( y = 18h + 0.05s \)[/tex]
- C. [tex]\( y = \frac{h}{18} + 5s \)[/tex]
- D. [tex]\( y = \frac{h}{18} + \frac{4}{5} \)[/tex]
The correct equation is:
[tex]\[ \boxed{B. \; y = 18h + 0.05s} \][/tex]
