A man has some hens and cows. If the number of heads be 48 and the number of feet equals 140, then the number of hens will be:
22
23
24
26
Explanation:
Let the number of hens be $ x $ and the number of cows be $ y $.
Then, $ x $ + $ y $ = 48 .... (i)
and 2$ x $ + 4$ y $ = 140 $\Rightarrow$ $ x $ + 2$ y $ = 70 .... (ii)
Solving (i) and (ii) we get: $ x $ = 26, $ y $ = 22.
$\therefore$ The required answer = 26.