Question

Farmer Bob has pigs and chickens. He has 37 animals, and there are 124 legs among them altogether. How many chickens does Bob have? A. 25 B. 4 C. 12 D. –4

Answer 1

For this case we have that the pigs have 4 legs while the hens have 2.

We propose a system of equations:

x: Variable representing the number of pigs

y: Variable representing the number of chickens

$x + y = 37\\4x + 2y = 124$

We multiply by -4 the first equation:

$-4x-4y = -148$

We add the equations:

$-4x-4y = -148\\4x + 2y = 124\\-4y + 2y = -148 + 124\\-2y = -24\\y = \frac {24} {2}\\y = 12$

So, there are 12 chickens.

$x + 12 = 37\\x = 37-12\\x = 25$

There are 25 pigs.

ANswer:

25 pigs

12 chickens

Option C

Answer 2

C. bc chickens have two legs each making it 12 chickens times 2 legs equal 24 plus the remaining 25 animals (pigs) would be 25x4=100+24 chicken legs = 124