# Practice pack

## Try these before reading the answers
Data: 2, 3, 3, 4, 18.
1. What is the median?
2. What is the mean? Show your calculation.
3. Replace 18 with 38. Which values change?
4. A learner says the median must increase because the total increased. Explain the mistake.

---

## Answer key
1. Median: 3, the third sorted value.
2. Mean: (2 + 3 + 3 + 4 + 18) / 5 = 30 / 5 = 6.
3. Mean: (2 + 3 + 3 + 4 + 38) / 5 = 50 / 5 = 10. Median stays 3.
4. Median follows the middle position, not the total. The changed number remains the largest.

## Follow-up
Create a different five-number example in which changing one number changes the median. Explain which number moves through the middle position.