Let's break down the solution step by step:
### (a) Frequency Distribution
First, we need to complete the frequency distribution for the cell phone models sold yesterday. The list of models sold is:
B, D, D, A, C, B, C, A, B, D, B, D, D, B, C, D, C, B, B, A, A
We will count the occurrences of each model:
- Model A: Count the number of 'A's.
- There are 4 'A's (A appears four times).
- Model B: Count the number of 'B's.
- There are 7 'B's (B appears seven times).
- Model C: Count the number of 'C's.
- There are 4 'C's (C appears four times).
- Model D: Count the number of 'D's.
- There are 6 'D's (D appears six times).
Now, we can complete the frequency distribution table:
[tex]\[
\begin{tabular}{cr}
Model & Frequency \\
\hline
A & 4 \\
B & 7 \\
C & 4 \\
D & 6 \\
\end{tabular}
\][/tex]
### (b) Number of Phones Supporting Clear1 Plan
The Clear1 plan is available for models B and D. To determine how many cell phones sold yesterday can use the Clear1 plan, we add the frequencies of models B and D:
- Frequency of model B: 7
- Frequency of model D: 6
Adding these counts together:
[tex]\[ 7 (model \ B) + 6 (model \ D) = 13 \][/tex]
So, 13 phones sold at Tom's Electronics yesterday can use the Clear1 plan.