what percent of r is s?

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by beatthegmatinsept » Thu Sep 09, 2010 7:56 am
Is it A?

a) r - s = 0
r = s, So r is 100% of s.

b) 3r + 4s = 7
2 variables, one quation. Can't find the value of r and s based on the information above.
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by kvcpk » Thu Sep 09, 2010 7:56 am
neerajkumar1_1 wrote:what percent of r is s?

1) r -s =0
2) 3r + 4s = 7
Wrong Thread. Request Moderator to move this to DS.

What percent of r is s?
assume x percent.
xr/100 = s
x= 100s/r

stmt1 says r=s
Hence x=1
SUFF

stmt2 says 3r+4s=7
We donot have any strict condition of whther r and s are positive/negative/fractions etc..
Hence many r and S can satisfy this eqtn.
hence INSUFF

pick A.

Hope this helps!!
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by neerajkumar1_1 » Thu Sep 09, 2010 8:13 am
sry abt the thread..
REquest moderator to put the topic in the correct thread...

the question is as such simple...

but my only doubt was if r = s
and we consider r=0

then wont r/s be undefined???

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by kvcpk » Thu Sep 09, 2010 9:25 am
neerajkumar1_1 wrote:sry abt the thread..
REquest moderator to put the topic in the correct thread...

the question is as such simple...

but my only doubt was if r = s
and we consider r=0

then wont r/s be undefined???
Thats a good question.

Let me explain this for you.
Our main goal is to find what percent of r is s?
But not 100r/s.

0 is 100% of 0.

Question is not asking us the values of 100r/s. So we should first see if 100r/s is satisified, if not then check with the main question once. Only then we can disqualify a statement.

We need to be careful when we are translating the words into eqtns.

Hope this helps!!
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don't be afraid of failure and don't abandon it.
People who work sincerely are the happiest."
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by tpr-becky » Fri Sep 10, 2010 10:50 am
This question asks for the value of an equation (What is r/s). When that happens you need to look at manipulating the equations offered.

1) can be reworked to r=s so we we know that r/s=1 (AD)

2)we cannot manipulate this equation to put is back into the fraction so pick A.
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