In a zoo, there are rabbits and pigeons. If their heads are counted, these are 90 while their legs are 224. Find the number of pigeons in the zoo.

Let us assume all 90 are rabbits, thus there must be 360 legs (Rabbits have 4 legs and pigeons have 2)

But there are $$360-224=136$$ less legs, so rabbits must be less.

=> Number of pigeons = $$\frac{136}{2}=68$$

Alternate Method : Let number of pigeons be $$x$$ and number of rabbits be $$y$$

=> $$x+y=90$$ -----------(i)

and $$2x+4y=224$$ ------(ii)

Solving the two equations, we get : $$x=68$$ and $$y=22$$

=> Ans - (B)