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There are some fishes in the pond. 15% of the fishes in pond died due to pollution in the pond. 25% were eaten up by the birds. 25% of the remaining fishes were caught by a fisherman. How many fishes were there in the beginning if 90 fishes are left in the pond?

There are some fishes in the pond. 15% of the fishes in pond died due to pollution in the pond. 25% were eaten up by the birds. 25% of the remaining fishes were caught by a fisherman. How many fishes were there in the beginning if 90 fishes are left in the pond? Correct Answer 200

Let the number of fishes in the pond be x.

Number of fishes that died due to pollution = 15% of x

Number of fishes that were eaten up by the birds = 25% of x

Number of fishes left in the pond = x - (15% of x + 25% of x) = 60% of x

Number of fishes caught by the fisherman = 25% of (60% of x) = 15% of x

In the end, there are 90 fishes left in the pond which is equal to (100 - 15 - 25 - 15) % of x = 45% of x

45% of x = 90

⇒ x = 200

∴ There were 200 fishes in the pond in the beginning.

Related Questions

Below are given four statements followed by four conclusions. You have to take the given statements to be true even if they appear to be at variance with commonly known facts, and then decide which of conclusions logically follows from the given statements. For each question, mark out an appropriate answer choice that you think is correct. Statements: Some wings are large. All large are birds. Some birds are kites. Some kites are not big. Conclusions: I. Some wings are birds. II. Some kites are birds. III. Some birds are large. IV. All wings can be large.
S1:Sun birds are among the smallest of Indian birds.
P :Though they are functionally similar to the humming birds of the New World, they are totally unrelated.
Q :They do eat insects too.
R :They are also some of the most brilliantly coloured birds.
S :sun birds feed on nectar mostly and helped in pollination.
S6:Our common sun birds are the purple sun bird, the glossy black species and purple rumped sun bird, the yellow and maroon species.

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