Final answer:
It will take 400 minutes for the temperature to decrease by 5°F, calculated by dividing 5°F by the rate of ¾°F/h, resulting in 6.6667 hours, which is then converted into minutes (6.6667 hours × 60 minutes/hour = 400 minutes).
Step-by-step explanation:
To calculate the time it will take for the temperature to decrease by 5°F, knowing that the temperature decreases at a rate of ¾ of a degree per hour, we can use the following steps:
Divide the total desired temperature decrease (5°F) by the rate of temperature decrease per hour (¾°F/h).
Calculate the total hours required for a 5°F decrease.
Since we want to find the time in minutes, we multiply the hours by 60 (as there are 60 minutes in an hour).
Step 1: 5°F divided by ¾°F/h = 5 ÷ 0.75 = 6.6667 hours
Step 2: 6.6667 hours are needed.
Step 3: 6.6667 hours × 60 minutes/hour = 400 minutes
Therefore, it will take 400 minutes for the temperature to decrease by 5°F.