Pool & Sauna

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Pool & Sauna

by crackgmat007 » Sun Jul 12, 2009 2:49 pm
Pls explain.
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by truplayer256 » Sun Jul 12, 2009 3:09 pm
There are a total of x members.
y members use the pool.

.30(x)= Use both the pool and sauna
.40(y)= Use only pool
.60(y)= Use both the pool and sauna

We want what how many of the x members use the pool, so technically, we want y/x.

.60(y)=.30(x)

y/x=.30/.60=1/2

1/2*100= 50%

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Re: Pool & Sauna

by dtweah » Sun Jul 12, 2009 3:12 pm
crackgmat007 wrote:Pls explain.
If 40% of those who use the pool don't use the Sauna, then 60% of those who use the pool use the sauna.

30=60%P

P=50%

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by crackgmat007 » Sun Jul 12, 2009 4:43 pm
.30(x)= Use both the pool and sauna
.60(y)= Use both the pool and sauna
I am actually confused with the above. I started off with the below equation:

P + S - B = 100

Based on the details in the question; P - B = 40; and B = 30, then P = 70. I guess I am missing something here.

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by tom4lax » Mon Jul 13, 2009 10:49 am
Using a double matrix for this problem is quite effective. Doing so would leave us with the equation below:

30% + 40%x = x

30% = 60%x

x = 50%