Question

At a shopping mall, the air conditioner is set so that it reduces temperature at the rate of \[4^\circ C\] every hour. If at 10 a.m. the temperature inside the mall was \[35^\circ C\], what will be the temperature inside the mall at 6 p.m.?
A.\[4^\circ C\]
B.\[6^\circ C\]
C.\[3^\circ C\]
D.\[7^\circ C\]

Answer 1

Hint: Here, we will find the difference in time between 10 a.m. and 6 p.m. Then we will multiply the time with the reduction rate of degree to find the reduction in temperature. Then by subtracting the reduction in temperature from the temperature at 10 a.m., we will get the temperature inside the mall at 6 p.m.

Complete step-by-step answer:
We are given that at a shopping mall, the air conditioner reduces temperature at the rate of \[4^\circ C\] every hour.
It is that at 10 a.m. the temperature inside the mall was \[35^\circ C\].
Now, we have to find the temperature inside the mall at 6 p.m.
We will find the difference in time to find the decrease in temperature.
Difference in Time between 10 a.m. and 6 p.m. \[ = 8\] hours
Temperature reduces at the rate of \[4^\circ C\] every hour.
So, Reduction in Temperature for \[8\] hours is found by multiplying the reduction in temperature for every hour by the number of hours.
Reduction in Temperature for 8 hours \[ = 8 \times 4^\circ C\]
Multiplying the terms, we get
\[ \Rightarrow \] Reduction in Temperature for 8 hours \[ = 32^\circ C\]
Now, we will find the temperature inside the mall at 6 p.m. by subtracting the reduction in Temperature from the temperature at 10 a.m.
The temperature inside the mall at 6 p.m. \[ = 35^\circ C - 32^\circ C\]
\[ \Rightarrow \] The temperature inside the mall at 6 p.m. \[ = 3^\circ C\]
Therefore, the temperature inside the mall at 6 p.m. will be \[3^\circ C\].
Thus, option (C) is the correct answer.

Note: While finding the difference between the time in hours we should convert the time in \[24\] hour format. This would make \[10A.M.\] as \[10:00\] hrs and \[6P.M.\] as \[18:00\] hrs. Now, by subtracting the previous time from the later time, we get the difference between the time as \[8\] hours. We know that Temperature is defined as a measure of hotness or coldness of a body.