Answer :
To find the median of the data set 21, 42, 63, 84, 105, 126, 147, you should follow these steps:
1. Identify the Data Set: The numbers in the data set are already ordered from smallest to largest: 21, 42, 63, 84, 105, 126, 147.
2. Determine the Number of Data Points: There are 7 numbers in the data set.
3. Identify Whether the Number of Data Points is Odd or Even: Since there are 7 (an odd number) data points, the median will be the number that is exactly in the middle of the list.
4. Find the Middle Number: As there are 7 data points, the middle number is the fourth number in this ordered list. So, start counting from the first:
- 1st number: 21
- 2nd number: 42
- 3rd number: 63
- 4th number: 84
- 5th number: 105
- 6th number: 126
- 7th number: 147
The fourth number is 84.
5. Conclusion: Since the middle number in this data set is 84, the median of this data set is 84.
Therefore, the correct answer is OC. 84.
1. Identify the Data Set: The numbers in the data set are already ordered from smallest to largest: 21, 42, 63, 84, 105, 126, 147.
2. Determine the Number of Data Points: There are 7 numbers in the data set.
3. Identify Whether the Number of Data Points is Odd or Even: Since there are 7 (an odd number) data points, the median will be the number that is exactly in the middle of the list.
4. Find the Middle Number: As there are 7 data points, the middle number is the fourth number in this ordered list. So, start counting from the first:
- 1st number: 21
- 2nd number: 42
- 3rd number: 63
- 4th number: 84
- 5th number: 105
- 6th number: 126
- 7th number: 147
The fourth number is 84.
5. Conclusion: Since the middle number in this data set is 84, the median of this data set is 84.
Therefore, the correct answer is OC. 84.
