Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.
Customized for You
we will pick new questions that match your level based on your Timer History
Track Your Progress
every week, we’ll send you an estimated GMAT score based on your performance
Practice Pays
we will pick new questions that match your level based on your Timer History
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Thank you for using the timer!
We noticed you are actually not timing your practice. Click the START button first next time you use the timer.
There are many benefits to timing your practice, including:
Prefer video-based learning? The Target Test Prep OnDemand course is a one-of-a-kind video masterclass featuring 400 hours of lecture-style teaching by Scott Woodbury-Stewart, founder of Target Test Prep and one of the most accomplished GMAT instructors
Still interested in this question? Check out the "Best Topics" block below for a better discussion on this exact question, as well as several more related questions.
Let say height of the smaller triangle is h...and that of the larger triangle is H. So s/S=h/H=k where K is a constant (as per rules of similarity)...so s=KS and h=kH Now 1/2*s*h=1/2*1/2*S*H ie...s*h=1/2*S*H ie...KS*KH=1/2*S*H ie...K^2 =1/2 ie...K=1/(sqrt 2) ie...s/S = 1/(sqrt 2) so S=(Sqrt 2)s
While the two previous posts provide the correct answer, I'm going to provide a bit more narration through my answer to hopefully help others. I saw this on the GMATPrep 2 and got it wrong but it's a much simpler problem than it appears to be.
We're asked to find in terms of \(S\). We need to remember this for later.
If we make the height of s the variable \(a\), and let the height of S be \(b\) (similar to making it h and H)
Lets use a formula for the area of each triangle.
s = 1/2 * s * a
S = 1/2 * S * b
Now we also know that the proportion of a:b is the same as s:S. (This will be important later)
so to make an equation where we can solve for \(S\), we need get S on one side. To do this, we must make it 2s = S because s is 1/2 the area of S. It's not as simple to just answer E on the problem 2s because we've not taken into account the values of the height of each triangle.
Now substitute in from above
2 * 1/2 * s * a = 1/2 * S * b 2sa = Sb (the 1/2 on each side cancels out)
now, if we divide each side by Sa we get
2s/S = b/a
We know that a:b or a/b = s/S, so b/a = S/s, we can substitute these values in.
2s/S = S/s, now get a single s on one side and you have your answer. To get rid of the fractions, we can cross multiply.
\(2s^2 = S^2\)
Take the square root of both sides \(\sqrt{2}s = S\)
Archived Topic
Hi there,
This topic has been closed and archived due to inactivity or violation of community quality standards. No more replies are possible here.
Still interested in this question? Check out the "Best Topics" block above for a better discussion on this exact question, as well as several more related questions.