Tuesday, September 27, 2011

Maths Ws 9 Q4 (Challenging Questions)

104 chickens and goats in a farm have 246 legs altogether. How many chickens and goats are there in the farm?

Assuming the number of chickens is 'x'
Assuming the number of goats is 'y'

x + y = 104
2x + 4y = 246 ( The number of legs time the number of animals)

(2x + 4y) - 2(x + y) = 2y
246 - 2(104) = 246 -208 = 38  (38 is 2y)      <-- ( Substituting algebraic terms for numbers)
38/2 = 19

y = 19

104 - 19 = 85

x = 85

So, the number of chickens is 85 and the number of goats is 19.

Done by Tobias Tang (22) 27/9/11

5 comments:

  1. Simple, easy to understand

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  2. Detailed solution, easy to understand

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  3. Very simeple too understand,very straightforward

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  4. someone called abiyyu had just9/28/2011 10:36:00 AM

    good but can be improved:
    1. you can say that (2x+4y)-2(x+y)=246-2(104) and then solve this equation because if you do it separately, some people might not be able to visualize that the two are the same.
    2. if possible, you can say what is the result of every equation.

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  5. i agree with "someone called abiyyu". it's rather simple to understand visually

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