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In the figure above, what is the area of region PQRST ? (1) PQ = RS (
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26 Apr 2019, 03:09
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In the figure above, what is the area of region PQRST ? (1) PQ = RS (2) PT = QT DS74602.01 OG2020 NEW QUESTION Attachment:
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In the figure above, what is the area of region PQRST ? (1) PQ = RS (
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Updated on: 04 May 2019, 10:42
The Logical approach to this question will the observation that the area we're looking for is of a shape which doesn't have a matching formula. Thus, we should either refer to it as the sum of or the difference between two familiar shapes. In this case, the sum of a rectangle and a triangle. Statement (1) tells us that the sides of the rectangle are 6, which is enough to find the other side of the rectangle (using the pythagorean triplet 6,8,10). However, we don't have a height required to find the area of the triangle. Thus, answers (A) and (D) are eliminated. Statement (2): Knowing that the triangle is an isosceles triangle is not enough to find its area. Answer choice (B) is eliminated. Combining both statements, we now know that the triangle is an equilateral triangle, so the length of one side is enough to find its area. The correct answer is (C). Posted from my mobile device
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Re: In the figure above, what is the area of region PQRST ? (1) PQ = RS (
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01 May 2019, 07:41
Please explain why statement 2 is insufficient: Since we know the isosceles triangle. Side QT = RS, and Side QR can be found using Pythagorean theorem. Hence, it can be found. Thanks.



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In the figure above, what is the area of region PQRST ? (1) PQ = RS (
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01 May 2019, 08:56
Valhalla wrote: Please explain why statement 2 is insufficient: Since we know the isosceles triangle. Side QT = RS, and Side QR can be found using Pythagorean theorem. Hence, it can be found. Thanks. Hey Valhalla, Knowing that QT= RS is insufficient to know their length. (In particular, it is also insufficient to calculate QR) Try it! Draw PT of length 6, build an isosceles triangle on top of it and build the square QRST off the side of that. See how changing the lengths of the sides of the isosceles means that you will change the size of the square (because the diagonal must equal 10). Then this is insufficient.
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Re: In the figure above, what is the area of region PQRST ? (1) PQ = RS (
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01 May 2019, 17:14
Thanks. I have mistakenly taken PT = QT = 6, that is why I could not fathom how statement 2 alone is insufficient. Dear David, thanks for replying. Any pointers you would give to avoid such mistakes? Thanks.



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In the figure above, what is the area of region PQRST ? (1) PQ = RS (
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02 May 2019, 02:29
Valhalla wrote: Thanks. I have mistakenly taken PT = QT = 6, that is why I could not fathom how statement 2 alone is insufficient. Dear David, thanks for replying. Any pointers you would give to avoid such mistakes? Thanks. Hey Valhalla, The mistake you describe is what we classify as a 'silly mistake'. In other words, it is not that you didn't know the material, but rather that you missed / misinterpreted a small piece of data and therefore got the rest of the question wrong. Tip number 1: Take a few seconds after reading the question but before diving into calculations to make sure you've copied everything down / read everything correctly. This is the best way to avoid such mistakes. Tip number 2: Build up a timing strategy which doesn't leave you feeling completely rushed. It is better to guess a few questions and have enough time to do the others properly than to do everything in a hurried manner. Tip number 3: Practice! The more questions you solve, the more familiar with the GMAT you get, and consequently the better you are able to notice the 'important' and 'tricky' details. Best of luck, David
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Re: In the figure above, what is the area of region PQRST ? (1) PQ = RS (
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03 May 2019, 11:10
Why is statement 1 insufficient? We have diagonal as 10 and PQ=RS=6 So, we can find ST = 8 Since its a rectangle, we can directly find the area of this figure. Similarly, for the triangle, we can take height which is divides QT in half and so by pythagoras, we can find the height of triangle as 5.
What have I considered wrong here?



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Re: In the figure above, what is the area of region PQRST ? (1) PQ = RS (
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03 May 2019, 12:21
abannore wrote: Why is statement 1 insufficient? We have diagonal as 10 and PQ=RS=6 So, we can find ST = 8 Since its a rectangle, we can directly find the area of this figure. Similarly, for the triangle, we can take height which is divides QT in half and so by pythagoras, we can find the height of triangle as 5.
What have I considered wrong here? Hey abannore, You're right about the rectangle but wrong about the triangle. The height only divides QT in half if the triangle is isosceles (if PQ = PT). One way to SEE that there are many options is to imagine different angles for PQT. If angle PQT were exactly 90 degrees, then PQ itself would be the height! Instead, if angle PQT was very close to 0 then the triangle would be very 'narrow', and the height would also be very close to 0. Two different options > insufficient. Best, David
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Re: In the figure above, what is the area of region PQRST ? (1) PQ = RS (
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03 May 2019, 22:36
DavidTutorexamPAL wrote: The Logical approach to this question will the observation that the area we're looking for us of a shape which doesn't have a matching formula. Thus, we should either refer to it as the sum of or the difference between two familiar shapes. In this case, the sum of a rectangle and a triangle. Statement (1) tells us that the sides of the rectangle are 6, which is enough to find the other side of the rectangle (using the pythagorean triplet 6,8,10).Yet, we don't have a height required to find the area of the rectangle. Thus, answers (A) and (D) are eliminated. Statement (2): Knowing that the triangle is an isoscelous triangle is not enough to find its area. Answer choice (B) is eliminated. Combining both statements, we now know that the triangle is an equilateral triangle, so one side is enough in order to find its area. The correct answer is (C).
Posted from my mobile device Hi David, do you mean triangle here?



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In the figure above, what is the area of region PQRST ? (1) PQ = RS (
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04 May 2019, 10:40
rnn wrote: DavidTutorexamPAL wrote: The Logical approach to this question will the observation that the area we're looking for us of a shape which doesn't have a matching formula. Thus, we should either refer to it as the sum of or the difference between two familiar shapes. In this case, the sum of a rectangle and a triangle. Statement (1) tells us that the sides of the rectangle are 6, which is enough to find the other side of the rectangle (using the pythagorean triplet 6,8,10).Yet, we don't have a height required to find the area of the rectangle. Thus, answers (A) and (D) are eliminated. Statement (2): Knowing that the triangle is an isoscelous triangle is not enough to find its area. Answer choice (B) is eliminated. Combining both statements, we now know that the triangle is an equilateral triangle, so one side is enough in order to find its area. The correct answer is (C).
Posted from my mobile device Hi David, do you mean triangle here? Hey rnn, You mean in (1)? Yes! Thanks, fixed the typo.
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Re: In the figure above, what is the area of region PQRST ? (1) PQ = RS (
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11 May 2019, 14:25
Hi All, We're asked for the area of region PQRST. This question is based around a couple of Geometry rules. To properly find the area, we can break this shape into 2 pieces (a rectangle and a triangle), so we need to know the dimensions of the rectangle and the exact type of triangle  since we have one of the sides, we either need the 3 angles or the 2 missing sides  to calculate the overall area. (1) PQ = RS With the information in Fact 1, we know that the width of the rectangle is 6 and one of the two missing triangle sides is also 6. Along with the diagonal of the rectangle, we can now calculate its length (it's 8, since we have a 6/8/10 right triangle in the rectangle) but without the 3rd side of the triangle (or its 3 angles), we cannot calculate that other area. Fact 1 is INSUFFICIENT (2) PT = QT The information in Fact 2 tells us that the triangle is either Isosceles or Equilateral, but we still do not know enough to determine its area and we don't know the length or width of the rectangle, so we cannot determine its area either. Fact 2 is INSUFFICIENT Combined, we know... PQ = RS PT = QT With both Facts, we know that the triangle's sides are 6/6/6, so it's Equilateral and we can calculate its area. We also know the area of the rectangle (it's 6x8 = 48), so we CAN determine the area of PQRST. Combined, SUFFICIENT Final Answer: GMAT assassins aren't born, they're made, Rich
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Re: In the figure above, what is the area of region PQRST ? (1) PQ = RS (
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15 Nov 2019, 12:18
Hi everyone.
I have a “silly ques” why cant this alleged rectangle be a square? What property am I missing?
TIA
Sambhav
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Re: In the figure above, what is the area of region PQRST ? (1) PQ = RS (
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15 Nov 2019, 12:32
DavidTutorexamPAL wrote: abannore wrote: Why is statement 1 insufficient? We have diagonal as 10 and PQ=RS=6 So, we can find ST = 8 Since its a rectangle, we can directly find the area of this figure. Similarly, for the triangle, we can take height which is divides QT in half and so by pythagoras, we can find the height of triangle as 5.
What have I considered wrong here? Hey abannore, You're right about the rectangle but wrong about the triangle. The height only divides QT in half if the triangle is isosceles (if PQ = PT). One way to SEE that there are many options is to imagine different angles for PQT. If angle PQT were exactly 90 degrees, then PQ itself would be the height! Instead, if angle PQT was very close to 0 then the triangle would be very 'narrow', and the height would also be very close to 0. Two different options > insufficient. Best, David Posted from my mobile device



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Re: In the figure above, what is the area of region PQRST ? (1) PQ = RS (
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15 Nov 2019, 14:53
Sam10smart wrote: Hi everyone.
I have a “silly ques” why cant this alleged rectangle be a square? What property am I missing?
TIA
Sambhav
Posted from my mobile device Hi Sambhav, In my explanation (which is right above yours), I work through that the information in Fact 1 proves that the rectangle is a 6x8 (and not a square). I didn't go through that extra work in Fact 2 because it wasn't necessary  BUT the information in Fact 2 does not restrict the rectangle to a 6x8. With Fact 2, we could actually be dealing with a square (if the sides were 5√2, then we would have a square and an isosceles triangle (with a different total area than if we had a 6x8 rectangle and triangle). GMAT assassins aren't born, they're made, Rich
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Re: In the figure above, what is the area of region PQRST ? (1) PQ = RS (
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27 Nov 2019, 22:13
Hello All,
How can we came to conclusion that QRST is rectangle? Does four angles =90 degree is sufficient condition for a figure to be rectangle? As we don't have any information that opposite sides are equal or parallel
Thanks



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Re: In the figure above, what is the area of region PQRST ? (1) PQ = RS (
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29 Nov 2019, 12:44
Hi anand.prakash90, Yes  when dealing with a 4sided shape, if all four angles are 90degree angles, then the sides ARE parallel and the shape IS a rectangle (and might actually be a square, which is ultimately a specific type of rectangle). GMAT assassins aren't born, they're made, Rich
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Re: In the figure above, what is the area of region PQRST ? (1) PQ = RS (
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