The total force in each direction has to be the same.
The total force of the blue team is
(220 + 340 + 180 + 560) = 1,300 N
The three members of the red team add up to
(250 + 160 + 420) = 830 N
In order to exactly match the 1,300 N of the blue team,
the fourth red-team guy must contribute an additional
(1,300 - 830) = 470 N .