Because two people caught 20 fish, and in the end there were as many as 10 each, so the first person gave the second person 4 fish, which became 10, so the first person originally had 14 fish, and the second person originally had 6 fish, plus the first person gave 4 fish, which became/kloc-0.

20÷2= 10 (article)

10+4= 14 (article)

10-4=6 (article)