EXPLANATION
IQ5. The zoo had some lions and some parrots. The supervisor counted 15 heads and 50 legs. How many lions were there?
a) 8
b) 10
c) 12
d) 13
ANSWER: b) 10
EXPLANATION:
Let's assume the number of lions as "L" and the number of parrots as "P."
Each lion has one head and four legs, while each parrot has one head and two legs. Given that there are a total of 15 heads and 50 legs, we can set up the following equations:
L + P = 15 (Equation 1: Total number of heads)
4L + 2P = 50 (Equation 2: Total number of legs)
Now we can solve this system of equations to find the values of L and P.
From Equation 1, we can isolate P:
P = 15 - L
Substituting this value into Equation 2:
4L + 2(15 - L) = 50
Simplifying the equation:
4L + 30 - 2L = 50
Combining like terms:
2L + 30 = 50
Subtracting 30 from both sides:
2L = 20
Dividing both sides by 2:
L = 10
Therefore, there are 10 lions in the zoo.
