Goat chicken puzzle

There were goats and chickens in the yard. The total number of heads was 15, and the total number of legs was 40. Calculate the number of hens. Every animal has all its legs.

Final Answer:

a =  5
b =  10

Step-by-step explanation:


a+b=15
4a+2b=40

a+b=15
4·a+2·b=40

a+b = 15
4a+2b = 40

Pivot: Row 1 ↔ Row 2
4a+2b = 40
a+b = 15

Row 2 - 1/4 · Row 1 → Row 2
4a+2b = 40
0.5b = 5


b = 5/0.5 = 10
a = 40-2b/4 = 40-2 · 10/4 = 5

a = 5
b = 10

Our linear equations calculator calculates it.



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