Question
A scuba diver used the expression below to describe his position in relation to sea level.
2 + (negative 20) + 8
Which statement could describe the diver’s movements?
Starting on a platform 2 feet above sea level, dive down to a location that is 18 feet below sea level, and then rise 8 feet.
Starting on a platform 2 feet above sea level, dive down to a location that is 20 feet below sea level, and then rise 8 feet.
Starting 2 feet below sea level, dive down 20 more feet, and then rise to a location that is 8 feet below sea level.
Starting 2 feet below sea level, dive down 18 more feet, and then rise to a location that is 8 feet below sea level.
2 + (negative 20) + 8
Which statement could describe the diver’s movements?
Starting on a platform 2 feet above sea level, dive down to a location that is 18 feet below sea level, and then rise 8 feet.
Starting on a platform 2 feet above sea level, dive down to a location that is 20 feet below sea level, and then rise 8 feet.
Starting 2 feet below sea level, dive down 20 more feet, and then rise to a location that is 8 feet below sea level.
Starting 2 feet below sea level, dive down 18 more feet, and then rise to a location that is 8 feet below sea level.
Answers
Answered by
GPT-4o mini
To analyze the expression \(2 + (-20) + 8\), we can break it down step by step:
1. **Starting Position:** The diver starts at 2 feet above sea level (which can be represented as +2).
2. **Movement Down:** The diver then dives down 20 feet (the negative sign indicates a descent). This would take the diver from +2 feet to -18 feet (2 feet - 20 feet = -18 feet).
3. **Movement Up:** Finally, the diver rises 8 feet from -18 feet. This would take the diver from -18 feet to -10 feet (-18 feet + 8 feet = -10 feet).
Now let's look at the provided statements:
1. **Statement 1:** Starting on a platform 2 feet above sea level, dive down to a location that is 18 feet below sea level, and then rise 8 feet.
- This is not correct, as it suggests diving to -18 feet instead of -20 feet as the change is not correctly represented.
2. **Statement 2:** Starting on a platform 2 feet above sea level, dive down to a location that is 20 feet below sea level, and then rise 8 feet.
- This is incorrect because from +2 feet, diving to -20 feet does not match the calculation order.
3. **Statement 3:** Starting 2 feet below sea level, dive down 20 more feet, and then rise to a location that is 8 feet below sea level.
- This statement is also incorrect because starting 2 feet below sea level would imply -2 feet initially. From -2 feet diving down 20 feet takes you to -22 feet, and then rising 8 feet takes you to -14 feet, which also does not match.
4. **Statement 4:** Starting 2 feet below sea level, dive down 18 more feet, and then rise to a location that is 8 feet below sea level.
- This is also incorrect because starting at -2, and diving down further (by what is implied) does not fit the movements described.
Based on the analysis, the most logically descriptive statement based on the movement outlined by the expression \(2 + (-20) + 8\) is:
**Correct Statement:** Starting on a platform 2 feet above sea level, dive down to a location that is 20 feet below sea level, and then rise 8 feet.
1. **Starting Position:** The diver starts at 2 feet above sea level (which can be represented as +2).
2. **Movement Down:** The diver then dives down 20 feet (the negative sign indicates a descent). This would take the diver from +2 feet to -18 feet (2 feet - 20 feet = -18 feet).
3. **Movement Up:** Finally, the diver rises 8 feet from -18 feet. This would take the diver from -18 feet to -10 feet (-18 feet + 8 feet = -10 feet).
Now let's look at the provided statements:
1. **Statement 1:** Starting on a platform 2 feet above sea level, dive down to a location that is 18 feet below sea level, and then rise 8 feet.
- This is not correct, as it suggests diving to -18 feet instead of -20 feet as the change is not correctly represented.
2. **Statement 2:** Starting on a platform 2 feet above sea level, dive down to a location that is 20 feet below sea level, and then rise 8 feet.
- This is incorrect because from +2 feet, diving to -20 feet does not match the calculation order.
3. **Statement 3:** Starting 2 feet below sea level, dive down 20 more feet, and then rise to a location that is 8 feet below sea level.
- This statement is also incorrect because starting 2 feet below sea level would imply -2 feet initially. From -2 feet diving down 20 feet takes you to -22 feet, and then rising 8 feet takes you to -14 feet, which also does not match.
4. **Statement 4:** Starting 2 feet below sea level, dive down 18 more feet, and then rise to a location that is 8 feet below sea level.
- This is also incorrect because starting at -2, and diving down further (by what is implied) does not fit the movements described.
Based on the analysis, the most logically descriptive statement based on the movement outlined by the expression \(2 + (-20) + 8\) is:
**Correct Statement:** Starting on a platform 2 feet above sea level, dive down to a location that is 20 feet below sea level, and then rise 8 feet.