A certain freezing process requires that room temperature be lowered from 40 �C at the rate of 5 �C every hour. What will be the room temperature 10 hours after the process begins?

It is given in the question that,


Initial temperature = 40oC


Also,


Change in temperature per hour = - 5oC


Therefore,


Change in temperature after 10 hours = (-5) × 10


= - 50oC


Hence,


Final temperature = 40oC + (-50oC)


= - 10oC


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