Can u pls explain?
They can occupy the 7 seats in the following manner:
234567 ( since the aisle seat always needs to get ocupied)
Hence, this can be done in 6! ways.. since we are considering two possibilities, its 6!*2 OR 6!+6!
You and gayathri have the same result, but I believe you each
interpreted the problem differently.
"One of them needs to sit in a seat along the aisle. "
I and gayathri interpreted this statement as there is
one particular person who must sit in one of the two aisle
seats. After that one person is assigned to an aisle seat,
there are 6 seats left for the 5 people. This interpretation
puts all six people in the row, but allows for an empty
seat between two of the friends (in other words, both
aisle seats can be occupied).
Unless I misunderstood your explanation, you are assuming that
there can be no empty seat between the friends occupying
the aisle and that any one of the six friends may be the
one on the aisle. These assumptions offset each other and
produce the same value of 1440.