In order for a bag of M\&M's to pass quality control, it must have at least 6 orange candies. Calculate the mean number of orange M\&M's in the small bags that passed quality control.

[tex]\[
\begin{array}{c|c}
\text{Orange M\&Ms in a bag} & \text{Frequency} \\
\hline
3 & 12 \\
4 & 19 \\
5 & 23 \\
6 & 71 \\
7 & 38 \\
8 & 37 \\
\end{array}
\][/tex]

A. 6.1
B. 5.9
C. 5.8
D. 6.8



Answer :

To determine the mean number of orange M&Ms in the small bags that passed quality control, let's follow the steps below:

1. Identify the bags that pass quality control: A bag passes quality control if it has at least 6 orange M&Ms. From the given table, these are the bags containing 6, 7, and 8 orange M&Ms.

2. Extract frequencies corresponding to the passing bags:
- Bags with 6 orange M&Ms: frequency = 71
- Bags with 7 orange M&Ms: frequency = 38
- Bags with 8 orange M&Ms: frequency = 37

3. Calculate the total number of bags that passed quality control:
[tex]\[ \text{Total passing bags} = 71 + 38 + 37 = 146. \][/tex]

4. Calculate the weighted sum of orange M&Ms in the passing bags:
- For 6 orange M&Ms: [tex]\(6 \times 71 = 426\)[/tex]
- For 7 orange M&Ms: [tex]\(7 \times 38 = 266\)[/tex]
- For 8 orange M&Ms: [tex]\(8 \times 37 = 296\)[/tex]

[tex]\[ \text{Weighted sum} = 426 + 266 + 296 = 988. \][/tex]

5. Calculate the mean number of orange M&Ms in the passing bags:
[tex]\[ \text{Mean} = \frac{\text{Weighted sum}}{\text{Total passing bags}} = \frac{988}{146} \approx 6.767. \][/tex]

Hence, the mean number of orange M&Ms in the bags that passed quality control is approximately 6.8. The correct answer is:

D. 6.8