Old McDonald had a farm. In one pen the old farmer had chickens and bulls together. In that pen there were 40 animals in total, but there were 130 legs. Can you figure out how many chickens and bulls are in that pen?

There are 15 numbers of chicken and 25 numbers of bulls.

Step-by-step explanation:

The pen had chickens and bulls. The pen contains 40 animals in total. The number of legs in the pen is 130.

Let

a = number of chicken

b = number of bull

a + b = 40 ... (i)

A chicken has 2 legs and a bull has 4 legs.

The total legs can be represented as

2a + 4b = 130 ... (ii)

combine the equation

a + b = 40 ... (i)

2a + 4b = 130 ... (ii)

a = 40 - b

insert the value of a in equation (ii)

2 (40 - b) + 4b = 130

80 - 2b + 4b = 130

80 + 2b = 130

2b = 130 - 80

2b = 50

divide both sides by 2

b = 50/2

b = 25

Insert the value of b in equation (i)

a + b = 40

a + 25 = 40

a = 40 - 25

a = 15

There are 15 numbers of chicken and 25 numbers of bulls.