Question: The zoo had some lions and some parrots. The supervisor counted 15 heads and 50 legs. How many lines and parrots in the zoo?
Question: The zoo had some lions and some parrots. The supervisor counted 15 heads and 50 legs. How many lines and parrots in the zoo?
Solution:
This problem can be solved by solving a set of two linear equations.
Let number of lions = x
number of parrots = y
It means number of total heads = x+y=15
number of legs for lions = 4x
number of legs for parrots = 2y
So, total legs = 4x+2y=50
So, we have two equations,
x+y=15 ————————————–(1)
4x+2y=50 ————————————(2)
Multiplication of equation (1) by 4 on both sides give,
4x+4y=60 ———————————–(3)
Subtracting eq 2 from eq 4, we get,
2y=60-50=10
or
y=5
So, there are 5 parrots !
Put y=5 in eq 1 , we get,
x+5=15
or x=15-5=10
So, there are 10 lions !