Question

At 10:00 a.m., the temperature was 15°F. Over the next three hours, the temperature
decreased by 15°F. Which of these statements are true? Select three that apply.
A. The temperature was 30°F at 1:00 p.m., calculated as 15+15.
B. The temperature was 0°F at 1:00 p.m., calculated as 15–15 or 15+(–15).
C. The change in temperature is represented by –15, indicating a decrease of 15
degrees.
D. The change in temperature is represented by +15, correctly indicating an increase.
E. The expression 15+(–15) represents the temperature at 1:00 p.m.
F. The expression 15+15 represents the temperature at 1:00 p.m., accurately showing
the Decrease.

Answer 1

To solve the problem, we need to determine the temperature at 1:00 p.m. starting from the initial temperature of 15°F at 10:00 a.m. and noting that the temperature decreases by 15°F over the next three hours.

Starting from 15°F:
- After a decrease of 15°F, the calculation looks like this:
15°F - 15°F = 0°F.

Now let's evaluate each of the statements to see which are true:

A. The temperature was 30°F at 1:00 p.m., calculated as 15+15.
**False** - This miscalculates the temperature as it adds rather than subtracts.

B. The temperature was 0°F at 1:00 p.m., calculated as 15–15 or 15+(–15).
**True** - Correctly calculates the final temperature after the decrease.

C. The change in temperature is represented by –15, indicating a decrease of 15 degrees.
**True** - The change of –15 indicates a decrease in temperature.

D. The change in temperature is represented by +15, correctly indicating an increase.
**False** - This statement misrepresents the decrease as an increase.

E. The expression 15+(–15) represents the temperature at 1:00 p.m.
**True** - This expression correctly represents the calculation of the temperature after the decrease.

F. The expression 15+15 represents the temperature at 1:00 p.m., accurately showing the Decrease.
**False** - This incorrectly adds instead of reflecting the decrease.

Thus, the three true statements are:
- **B. The temperature was 0°F at 1:00 p.m., calculated as 15–15 or 15+(–15).**
- **C. The change in temperature is represented by –15, indicating a decrease of 15 degrees.**
- **E. The expression 15+(–15) represents the temperature at 1:00 p.m.**