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xoritos September 14th, 2018 05:44 AM

Number of sheeps
 
A farmer rears sheep and chickens at his farm. The number of sheep is 1/3 the number of chickens. There are 96 fewer sheep legs than chicken legs. How many sheep are there at the farm?

My work:

Number of sheeps = S Number of Chickens = C

We know that there is one third of sheeps than chickens. so, (1/3)S = C

We know that there are 96 fewer sheep legs than chicken leg. so, 2C = 4S - 96

I got stuck here and couldn't get the correct answer.

skeeter September 14th, 2018 06:07 AM

Quote:

The number of sheep is 1/3 the number of chickens.
$\displaystyle S = \frac{C}{3} \implies C = 3S$

Quote:

There are 96 fewer sheep legs than chicken legs.
$\displaystyle 4S = 2C + 96$


substitute $3S$ for $C$ in the last equation ...

$\displaystyle 4S = 2(3S) + 96$

solve for $S$

xoritos September 14th, 2018 01:27 PM

Quote:

Originally Posted by skeeter (Post 598906)
$\displaystyle S = \frac{C}{3} \implies C = 3S$

I see where I made the mistake. One third of the total chicken.

Quote:

Originally Posted by skeeter (Post 598906)

4S=2C+96

substitute 3S for C in the last equation ...

4S=2(3S)+96

-2S = 96. I'm not sure about this.

Thank you.

Denis September 14th, 2018 04:20 PM

C = 3S [1]

2C - 4S = 96 [2]

Substitute [1] in [2]:
2(3S) - 4S = 96
6S - 4S = 96
2S = 96
S = 48 : C = 3S = 144

I think Skeeter made a typo...

...hmmm, think I'll have a snack of chicken legs :)

skipjack September 15th, 2018 12:49 AM

As each sheep's 4 legs are 2 fewer than 3 chickens' 6 legs, number of sheep = 96/2 = 48.

xoritos September 15th, 2018 05:05 AM

Thank you.


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