I need help

Question

The government of Mexico declared blue sharks an endangered species they put tags on 36 blue sharks and released them later the corral 130 blue sharks among those blue sharks 20 were tagged

Answer 1

You didn't tell us what the question is, but I think it's "how many blue sharks are there?"  Let P = the total population (number) of blue sharks.  The proportion is:

 

36         20

-----  =  -----

 P         130

 

Solve for P.