Sheila wants to test the reasonableness of her answer to the expression below by using compatible numbers,

- 8 + 19 + 8

Which equation would help Sheila do this?

A. 10 + 20 + 10

B. - 10 - 20 + 8

C. - 10 + 20 + 10

D. 10 + 20 - 8

5 answers

To test the reasonableness of her answer to the expression -8 + 19 + 8, Sheila should choose the equation with compatible numbers that are close to the original numbers.

Since the original numbers are 8, 19, and 8, Sheila should choose compatible numbers that are close to these, such as 10, 20, and 10.

Therefore, the equation that would help Sheila do this is A. 10 + 20 + 10.
A meteorologist used the expression below to describe how the temperature changed.

- 5 + (- 4)

Which statement could describe how the temperature changed?

A. The temperature was -5 degrees, then it increased 4 degrees.

B. The temperature was -5 degrees, then it decreased 4 degrees.

C. The temperature was 5 degrees, then it increased 4 degrees.

D. The temperature was 5 degrees, then it decreased 4 degrees.
To describe how the temperature changed based on the expression -5 + (-4), we need to evaluate the expression.

-5 + (-4) simplifies to -9.

Therefore, the temperature changed by decreasing 9 degrees.

The correct statement that describes how the temperature changed is B. The temperature was -5 degrees, then it decreased 4 degrees.
A scuba diver used the expression below to describe his position in relation to sea level.

2 + (- 20) + 8

Which statement could describe the diver's movements?

A. 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.

B. 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.

C. Starting 2 feet below sea level, dive down 20 more feet, and then rise to a location that is 8 feet below sea level.

D. Starting 2 feet below sea level, dive down 18 more feet, and then rise to a location that is 8 feet below sea level.
The expression 2 + (- 20) + 8 can describe the diver's movements as follows:

- The diver starts 2 feet above sea level.
- He then dives down 20 feet, which brings him to 18 feet below sea level.
- He then rises 8 feet, which brings him to 10 feet below sea level.

So the correct statement that describes the diver's movements is B. 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.