Sure! Let's walk through this step by step.
We are given the model:
[tex]\[ y = 0.8x \][/tex]
where:
- [tex]\( x \)[/tex] represents the number of cell phones sold, and
- [tex]\( y \)[/tex] represents the number of cell phone cases sold.
In this scenario, it's mentioned that the store sold 100 cell phones. So, we have:
[tex]\[ x = 100 \][/tex]
Now, we need to find how many cell phone cases were sold. To do this, we substitute the value of [tex]\( x \)[/tex] into the model equation:
[tex]\[ y = 0.8 \times 100 \][/tex]
Multiply 0.8 by 100:
[tex]\[ y = 80 \][/tex]
Therefore, the store sold 80 cell phone cases. So, the correct answer is:
B. 80