If Brian caught 400 fish in one trip, he caught 2*400=<<400*2=800>>800 fish in two trips.
Since Brian catches 2/5 times less fish than Chris per trip, Chris catches 2/5*400=<<2/5*400=160>>160 more fish in one fishing trip.
Chris's total number of fish in one trip is 400+160 = <<400+160=560>>560 fish.
In 10 trips, Chris catches 560*10=<<560*10=5600>>5600 fish.
If in his two trips Brian catches 800 fish, and he goes fishing twice as often as Chris, if Chris goes fishing 10 times, Brian will catch 800*10=<<800*10=8000>>8000 fish.
The total number of fish they'll catch if Chris goes fishing ten times is 8000+5600=<<8000+5600=13600>>13600
#### 13600