Answer: it will take 10 minutes to get back to room temperature.
Step-by-step explanation:
Let us assume that the room temperature is 25 degrees. The current temperature of the soup before the decrease would be 25 + 50 = 75 degrees.
The soup drop about 5 degrees every minute. This is a linear rate. The rate at which the temperature is decreasing is in arithmetic progression. The formula for determining the nth term of an arithmetic sequence is expressed as
Tn = a + (n - 1)d
Where
a represents the first term of the sequence.
d represents the common difference.
n represents the number of terms in the sequence.
From the information given,
a = 75 degrees
d = - 5 degrees (it is decreasing)
n = t
We want to determine how long it will take to get back to 25 degrees, . Therefore,
25 = 75 -5 (t - 1) = 75 - 5t
5t = 75 - 25 = 50
t = 50/5 = 10 minutes
