Question

There are 14 eyes and 20 legs in a room . assuming that there are only humankind dogs in the room. how many humans are there

Answer 1

Let the no. of humans be h and that of dog be d.

Given that there are 14 eyes, and we know that a man as well as a dog has 2 eyes. So we can say that,

2h + 2d = 14

h + d = 7 → (1)

And given that there are 20 legs in the room. We know that a man has 2 legs and a dog has 4 legs. So we can say that,

2h + 4d = 20

h + 2d = 10

From (1),

7 + d = 10

d = 3,

Then,

h = 7 - d

h = 4