Question

In a controlled atmosphere, a liquid cools at a constant rate in which its temperature changes by 16/25 degree Fahrenheit in 1/2 second. How long will it take the liquid to cool 40 degrees? Explain in words how you determined your answer. *

Answer 1

We know that the temperature changes 16/25 degrees in 1/2 second. To find how long it will take the liquid to cool 40 degrees we can use the rule of three:

`\begin{gathered} (16)/(25)\rightarrow(1)/(2) \\ 40\rightarrow x \end{gathered}`

Then:

`x=(40\cdot(1)/(2))/((16)/(25))=((40)/(2))/((16)/(25))=(125)/(4)`

Therefore it takes 125/4 seconds (or 31.25 seconds) to cool the liquid 40 degress.