If we indicate with the measure of the termometer at the time (expressed in minutes), the measure at and the (final) measured temperature of the owen we have...

(1)

In (1) there are two unknown parameters, (that we want to find) and (that we probably don't know). If we take into account the measured we have performed at and we write...

(2)

In (2) you have two equations in two unknown parameters, so you can solve it and find the requested ...

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