Question

Some students, during a study, caught, marked and released 80 fishes in a pond. Later 100 fishes were caught at random. Among these 40 were found to be marked. What the approximate number of fishes in the pond?

(a) 50 

(b) 100 

(c) 200 

(d) 4000

Answer 1

Correct option (c) 200 

Explanation :

According to Petersons Mark and Recapture method, the population (P) is given by P = m(r + u)/r, where m = number of marked fishes = 80 , r = number of marked fishes recaptured = 40 and u = number of unmarked fishes captured