Solution:
we are given that
6 people can sit together at 1 rectangular table.
2 tables are placed together, 10 people can sit together.
14 people can sit if three tables are put together.
It mean we get a sequence
6,10,14..........
So its making an arithmetic progression, where
First term
Common difference
Number of terms=number of table
As we know the nth term is given by the formula
Hence 402 people can sit.