SOLUTION: The ratio of chickens, lambs and cows is 1:2:4 respectively. If the total number of animals is 21 how many lambs are there?

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Question 1017981: The ratio of chickens, lambs and cows is 1:2:4 respectively.
If the total number of animals is 21 how many lambs are there?



Answer by Edwin McCravy(20060) About Me  (Show Source):
You can put this solution on YOUR website!
If x:y:z = a:b:c

Then

x%2F%28x%2By%2Bz%29=a%2F%28a%2Bb%2Bc%29, y%2F%28x%2By%2Bz%29=b%2F%28a%2Bb%2Bc%29, z%2F%28x%2By%2Bz%29=c%2F%28a%2Bb%2Bc%29


Let the number of chickens be x
Let the number of lambs be y
Let the number of cows be z
a:b:c = 1:2:4
x+y+z = 21
a+b+c = 1+2+4 = 7

x%2F%2821%29=1%2F%287%29, y%2F%2821%29=2%2F%287%29, z%2F%2821%29=4%2F%287%29

Multiply each through by 21

x=3, y=6, z=12

Edwin