To determine which group's data is unreliable, we need to compare the amount of oil removed by each group with the initial amounts provided. Each group started with 100 mL of vegetable oil and 100 mL of engine oil.
Let's evaluate each group's results:
- Group 1:
- Vegetable oil removed: 10 mL
- Engine oil removed: 20 mL
- Total removal: 10 mL + 20 mL = 30 mL
- This is within the initial provided amount (200 mL total), so the data for Group 1 is reliable.
- Group 2:
- Vegetable oil removed: 110 mL
- Engine oil removed: 130 mL
- Total removal: 110 mL + 130 mL = 240 mL
- This exceeds the initial provided amount (200 mL total), indicating that it is impossible for Group 2 to have removed more oil than was provided. Hence, the data for Group 2 is unreliable.
- Group 3:
- Vegetable oil removed: 60 mL
- Engine oil removed: 40 mL
- Total removal: 60 mL + 40 mL = 100 mL
- This is within the initial provided amount (200 mL total), so the data for Group 3 is reliable.
- Group 4:
- Vegetable oil removed: 80 mL
- Engine oil removed: 70 mL
- Total removal: 80 mL + 70 mL = 150 mL
- This is within the initial provided amount (200 mL total), so the data for Group 4 is reliable.
Based on this analysis, the group whose data is obviously unreliable is Group 2.
