#### Explanation:

This is geometric progression sequence of which , first term

is $a = 2400$ , common ratio is $r = 0.5$ number of terms is

$n = 5$ We know term $\therefore {t}_{n} = a \cdot {r}^{n - 1}$

:. t_5=2400*0.5^4=2400*1/2^4=2400/16= $150 After $4$years the computer will worth $150 [Ans]