Final answer:
The final temperature in the lab after 7 hours is 34°F. This is calculated by determining that the temperature decreases by a total of 14°F over the 7-hour period, subtracting from the initial temperature of 48°F.
Step-by-step explanation:
The question is asking to calculate the final temperature in a lab after it has been lowered by 0.5 degrees Fahrenheit every 15 minutes for a duration of 7 hours. To find the final temperature, we must first determine how many times the temperature is lowered over the 7 hour period.
Since there are 60 minutes in an hour, 7 hours equal 420 minutes. Dividing this by 15 minutes gives us 28 intervals where the temperature decreases by 0.5 degrees. Hence, the total decrease in temperature is 28 times 0.5 degrees which equals 14 degrees.
Starting with an initial temperature of 48 Fahrenheit, we subtract the total decrease of 14 degrees to find the final temperature:
Final temperature = Initial temperature - Total decrease
Final temperature = 48°F - 14°F = 34°F