Water 63

Boiler heated water at the rate of 6°c per minute for 14 minutes. It then cooled at the rate of 8°c per minute. What would be its temperature after 24 minutes if its original temperature was 40°c?

Correct answer:

t =  20 °C

Step-by-step explanation:

$$\begin{gathered} t_1=40\text{°C} \\ {t}_2=t_1+6\cdot 14=40+6\cdot 14=124\text{°C} \\ {t}_3=\min (100,t_2)=\min (100,124)=100\text{°C} \\ t=t_3-8\cdot (24-14)=100-8\cdot (24-14)=20\text{°C} \end{gathered}$$

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