Question

In a group of animals there are 10 cows, 15 goats and 25 buffaloes. The percentage of goats in the group is

Answer 1

Answer:

The farmer has 60 chickens in his farm.

Using the difference of 2 equations method to solve for 2 variables:

Let C =chickens and G= goats then the 2 equations (E) are:

E1 would be: C + G = 80 (total animals) and

E2 would be: (C x 2) + (G x 4) = 200 (total animal legs)

to eliminate the variable C multiply E1 times 2 and subtract it from E2 to yield E3:

E2: 2C + 4G = 200

E1: - 2C - 2G = -160

E3: 0 + 2G = 40

E3: G = 40 / 20 = 20 number of goats then:

E1: C + 20 = 80

E1: C = 80 - 20 = 60 chickens

The proof then is:

E2: (2 x 60) + (4 x 20) = 200 [120+80= 200