Sequences and Series

A cake is taken out of a $156^\circ$156°C oven and left to cool in a room with a constant temperature of $26^\circ$26°C.

As soon as it is taken out, the temperature of the cake drops by $2.5^\circ$2.5°C each minute.

a

What is the temperature of the cake after $8$8 minutes?

b

Write a recurrence relation that gives the temperature $T_n$`T``n` of the cake after $n$`n` minutes in terms of $T_{n-1}$`T``n`−1.

c

By how many degrees has the temperature of the cake dropped after half an hour?

d

Find the number of minutes it will take for the cake to reach room temperature.

Easy

Approx 6 minutes

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Use arithmetic and geometric sequences and series

Apply sequences and series in solving problems