Angles (GPREP)

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Source: — Data Sufficiency |

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by amitansu » Tue Jul 29, 2008 5:23 am
yes ans is 'D'.

let us assume angle PQR=Y; angle PRQ=Z and angle PRS=X

From 1:
y+z=150 since angle P is 30 given.
=>z=150-y

x=180-z
putting the value of z we have x=180-150+y=30+y
so, we know it is 30 degree greater than y.
sufficient.

Stem 2: given already y+z=150 i.e same as stem 1...so sufficient.

Amit

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by zagcollins » Tue Jul 29, 2008 9:53 am
can you make please make the explanation a tad simpler?

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by parallel_chase » Tue Jul 29, 2008 12:30 pm
The question can be rephrased:

What is the value of angle PQR and angle PRS?

First look at the question and understand the figure given.

Lets look at the figure as One triangle

Angle S =90

Therefore the remaining two angles can be 60, 30.

Statement I.

Angle QPR is 30 that means angle QPS is 60 and angle PQS is 30.

If angle PQS is 30 , angle PQR will also be 30 because we are talking about the same angle.

Triangle QPR = angle QPR + angle PQR + angle PRQ =180

Therefore,
30+30+angle PRQ =180

angle PRQ= 120

and also look at this angle PRS+angle PRQ =180 (angles formed on the same prependicular or straight line),

120+angle PRQ =180

angle PRS=60

Hence Sufficient.


Statement II.

sum of two angles is given. I think if you understood the above explanation you can easily understand this statement.

Let me know if you cant. I will guide you through.