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42 votes
42 votes
Old McDonald had a farm. And on that farm he had 38 animals, some

horses and some chickens. Altogether, there were 94 animal legs in the
farm. Solve for the number of Horses and Chickens.

Old McDonald had a farm. And on that farm he had 38 animals, some horses and some-example-1
User Kwicher
by
2.6k points

2 Answers

22 votes
22 votes

Answer:

There are 9 horses and 29 chickens.

Explanation:

a = animals

a = 38

h = horses

c = chickens

l = legs

l = 94

Equation 1: h + c = 38

Horses have 4 legs. Chickens have 2 legs.

Equation 2: 4h + 2c = 94

Manipulate the equations so that one of the coefficients are the same.

We will multiple Equation 1 by 2 so that both equations have 2c.

Equation 1: 2h + 2c = 76

Equation 2: 4h + 2c = 94

Subtract Equation 1 from Equation 2.

Equation 2 - Equation 1

(4h + 2c) - (2h + 2c) = 94 - 76

(4h - 2h) + (2c - 2c) = 94 - 76

2h = 18

h = 9

Substitute h into either equation to solve for c.

Equation 1: 2h + 2c = 76

Equation 1: 2(9) + 2c = 76

Equation 1: 18 + 2c = 76

Equation 1: 2c = 76 - 18

Equation 1: 2c = 76 - 18

Equation 1: 2c = 58

Equation 1: c = 29

Equation 2: 4h + 2c = 94

Equation 2: 4(9) + 2c = 94

Equation 2: 36 + 2c = 94

Equation 2: 2c = 94 - 36

Equation 2: 2c = 58

Equation 2: c = 29

There are 9 horses and 29 chickens.

User Fatlog
by
2.8k points
22 votes
22 votes

Answer:

Heya, your answer would be 52 horses, and 42 chickens.

Explanation:

By doing the long, long and I mean long process of adding 2 + 2 or 4 + 4 (due to the fact chickens have 2 legs and horses have 4), we get to 52 horse legs, and 62 chicken legs.

Adieu

User Mihir
by
3.2k points