It takes Boeing

$2$

$7$

$,$

$4$

$0$

$0$

$$hours to produce the fifth

$7$

$8$

$7$

$$jet$.$ The learning factor is

$8$

$0$

$\%$

$.$

$$Time required for the production of the eleventh

$7$

$8$

$7$

$$:

$1$

$1$

th unit time

$\_$

$\_$

$\_$

$\_$

$\_$

$$hours$.$ Please help me solve with an excel breaking out how it is solved.