Answer :
let x be the no. of chickens and y be no. of cows
given x+y=30
as chickens have 2 legs and cows have 4 legs, the total no. of legs become 2x+4y
given 2x+4y=74
impiles x+2y=37
x+y=30
implies y=7,x=23
given x+y=30
as chickens have 2 legs and cows have 4 legs, the total no. of legs become 2x+4y
given 2x+4y=74
impiles x+2y=37
x+y=30
implies y=7,x=23
let no. of chickens = x and no. of cows = y
the total no.of animals = 30
x+y = 30
x = 30-y -----------------------------------------------(equation 1)
total no.of legs = 74
since cows have 4 legs and chickens 2 so we get the equation as
2x+4y=74 ----------------------------------------------(equation 2)
substitute eq (1) in eq(2)
2(30-y)+4y=74
60y-2y+4y=74
2y = 74-60
2y = 14
y = 7
substitute y=7 in eq(1)
x+y=30
x+7=30
x=30-7 => x=23
therefore, no.of chickens=23 and no.of cows=7
the total no.of animals = 30
x+y = 30
x = 30-y -----------------------------------------------(equation 1)
total no.of legs = 74
since cows have 4 legs and chickens 2 so we get the equation as
2x+4y=74 ----------------------------------------------(equation 2)
substitute eq (1) in eq(2)
2(30-y)+4y=74
60y-2y+4y=74
2y = 74-60
2y = 14
y = 7
substitute y=7 in eq(1)
x+y=30
x+7=30
x=30-7 => x=23
therefore, no.of chickens=23 and no.of cows=7