( 1.6 * 15+2.0 * 15+ 1.8 * 10)/( 15+ 10) = 65438.
1.8 * 2000 = 3600kg
3600*7.5=27000 yuan
Answer; Each fish 1.8 kg, and the total weight of all fish is 3600 kg, so you can get 2700 yuan.
the second question
Let the big fish have x kilograms, then the small fish have (3600-X).
Get it according to the meaning of the question.
10x+6(3600-x)= 27000 x = 1350kg。
A big fish has 1350kg.