1. **State the problem:** We need to find the mean number of emails sent on days beginning with the letter S or T. 2. **Identify the days:** Days starting with S are Saturday and Sunday. Days starting with T are Tuesday and Thursday. 3. **List the email counts for these days:** - Tuesday: 8 - Thursday: 5 - Saturday: 9 - Sunday: 2 4. **Use the mean formula:** $$\text{Mean} = \frac{\text{Sum of values}}{\text{Number of values}}$$ 5. **Calculate the sum:** $$8 + 5 + 9 + 2 = 24$$ 6. **Calculate the number of days:** There are 4 days (Tuesday, Thursday, Saturday, Sunday). 7. **Calculate the mean:** $$\text{Mean} = \frac{24}{4}$$ 8. **Simplify the fraction:** $$\text{Mean} = \cancel{\frac{24}{4}} = 6$$ **Final answer:** The mean number of emails sent on days beginning with S or T is **6**.