Question

3.
Sush went to a beach with her friends. Before arriving at the beach Sush entered into a
quarrel with one of her friends. After the quarrel they decided that they would never stand
or sit adjacent to each other. Keeping this in mind one of her friends realised that if they
were to sit in a row at the beach they could still sit in 480 ways. How many friends had
accompanied Sush to the beach?
1) 5
2) 6
3) 4
4) 7​

Answer 1

Answer:

4 friends is the answer

plzz mark my answer as brainliest answer

Answer 2

Step-by-step explanation:

If the group consisted of n person's then possible number of ways when sush does not sit with one particular friend

=n! -2×(n-1)! =480

Now, n! -2×(n-1)!= 480

(n-1) !(n-2) =480

=2×3×4×5×4

=(n-1)!(n-2) =5!×4

hence there were 6 persons in the group including sush