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During a winter cold spell the temperature change was -1.2 f per hour for a period of 4.5 hours which expressions can be used to find the overall change in the temperature during that time period.

A.) 4.5 divided (-1.2) degrees Fahrenheit

B.) 4.5x (-1.2) degrees Fahrenheit

C.) 4.5 - (-1.2) degrees Fahrenheit

D.) (-1.2)+(-1.2)+(1.2)+(1.2) degrees Fahrenheit

E.) 4(-1.2)+(0.5)(-1.2) degrees Fahrenheit​

2 Answers

8 votes

Final answer:

The overall change in temperature is calculated by multiplying the hourly rate of temperature change by the total hours. The correct expression is B.) 4.5 × (-1.2) degrees Fahrenheit, which is also equivalent to E.) 4(-1.2) + (0.5)(-1.2) degrees Fahrenheit.

Step-by-step explanation:

To find the overall change in temperature during the winter cold spell where the temperature changes -1.2 degrees Fahrenheit per hour for a period of 4.5 hours, we need to use multiplication to calculate the total change in temperature over time. The correct expression is therefore the amount of change per hour multiplied by the number of hours:

B.) 4.5 × (-1.2) degrees Fahrenheit

This will give us the total change in temperature over the 4.5-hour period. The other expressions do not accurately represent the situation described. Specifically:

A.) 4.5 divided by (-1.2) degrees Fahrenheit is division, which doesn't apply here.

C.) 4.5 - (-1.2) degrees Fahrenheit suggests subtraction, which isn't appropriate for a rate over time.

D.) (-1.2) + (-1.2) + (1.2) + (1.2) degrees Fahrenheit doesn't account for 4.5 hours and also incorrectly adds positive and negative changes together.

E.) 4(-1.2) + (0.5)(-1.2) degrees Fahrenheit is mathematically equivalent to the correct expression B and thus also accurately represents the situation.

User Nick Dima
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3.5k points
13 votes

Answer:

B.) 4.5x (-1.2) degrees Fahrenheit

User Catarina
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3.3k points