Scholars caught marked and released 80 fishes in a pond. Later 100 fishes were caught at random. 40 of them were marked. The number of fishes in the pond is

Options

A. 50
B. 100
C. 200
D. 4000

Answer

C

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
r=number of marked fishes recaptured
u=number of unmarked fishes captured.
P=m(r+u)/r `" "`m=80
`=(80(40+60))/(40)" "r=40`
`=200 " "u=(100-40)`
`" "`=60