There are some cows and ducks in a park. The total number of heads is 60 and the total number of legs is 180. Find the number of cows and ducks respectively.

A30, 30 ✓ Correct

B32, 28

C28, 32

D24, 36

Correct answer: (A) 30, 30

Explanation

There are 30 cows and 30 ducks.

Let cows = c and ducks = d, with c + d = 60.

Legs give 4c + 2d = 180, so 2c + d = 90.

Subtracting the head equation: c = 30.

Then d = 60 - 30 = 30.

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