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.

It appears that you are browsing the GMAT Club forum unregistered!

Signing up is free, quick, and confidential.
Join other 500,000 members and get the full benefits of GMAT Club

Registration gives you:

Tests

Take 11 tests and quizzes from GMAT Club and leading GMAT prep companies such as Manhattan GMAT,
Knewton, and others. All are free for GMAT Club members.

Applicant Stats

View detailed applicant stats such as GPA, GMAT score, work experience, location, application
status, and more

Books/Downloads

Download thousands of study notes,
question collections, GMAT Club’s
Grammar and Math books.
All are free!

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:

If you see multiple addition or subtraction under the root, make sure you simplify that first and take square root of the total.

\(\sqrt{1+2-3+5-5+9} = \sqrt{9} = 3\)

However, \(\sqrt{mn} = \sqrt{m}*\sqrt{n}\)

For addition and subtraction, one can't split the terms as individual root term. And also the vice versa is not allowed(two split root terms can't be combined under one root)

For multiplication and division, one can split the terms as individual root term. Vice versa is also true.

I actually didn't get why you eliminated A, B, D. I think this method would be dangerous. Solving it entirely is better. Shouldn't take you more than 45 seconds if you practice a bit.

What if the question was: \sqrt{9^2+5^3+10^2+55}+\sqrt{20}

Shalom. I eliminated A, B, and D because they contain the sqrt{20} unsimplified. I am sure that solving it would be better I agree. I am only pointing out that I noticed A, B, and D could possibly be done away with using the process of elimination. The remaining two answers have the sqrt{20} broken down. If the question was \sqrt{9^2+5^3+10^2+55}+\sqrt{20} then I would consider the answer choices with the sqrt{20} simplified.

However, the answer to the question I asked is "A". \(\sqrt{9^2+5^3+10^2+55}+\sqrt{20} = 19+\sqrt{20}\)

I wouldn't advocate to guess in these simplify type of questions. Save the guessing and POE for relatively difficult questions.

But, if you are confident about your method; then please do so!!!
_________________

Made a stupid mistake and really shouldn't have since I factored 20 right away! Figured that 5 under the radical would matter and it did. Will go w/ my gut next time.
_________________

Made a stupid mistake and really shouldn't have since I factored 20 right away! Figured that 5 under the radical would matter and it did. Will go w/ my gut next time.

Just reworked problem. Remembered that I had to add the numbers under the radical before I could simplify anything.
_________________

The first part of D, 5 times sqrt of 100, is impossible to get if you factored correctly. If you add up all three terms you should get 125. The sq. root of 125 can be broken down into the square root of (5 x 5 x 5).

Shalom [b]Tell me if I am wrong but if I had to make an educated guess on this question I would chose E. If you breakdown the sqrt(20) that leaves 2*sqrt(5). The only possible answer would be E simply because three of the other four possible answers include the sqrt(20) unsimplified. [/b]

Shalom [b]Tell me if I am wrong but if I had to make an educated guess on this question I would chose E. If you breakdown the sqrt(20) that leaves 2*sqrt(5). By using the process of elimination you can get rid of three of the four possible answers. That would leave C and E. Then if I would have had to make a choice between these two I would chose E because it is the most simplified.

Shalom [b]Tell me if I am wrong but if I had to make an educated guess on this question I would chose E. If you breakdown the sqrt(20) that leaves 2*sqrt(5). By using the process of elimination you can get rid of three of the four possible answers. That would leave C and E. Then if I would have had to make a choice between these two I would chose E because it is the most simplified.

I actually didn't get why you eliminated A, B, D. I think this method would be dangerous. Solving it entirely is better. Shouldn't take you more than 45 seconds if you practice a bit.

What if the question was: \(\sqrt{9^2+5^3+10^2+55}+\sqrt{20}\)
_________________

I actually didn't get why you eliminated A, B, D. I think this method would be dangerous. Solving it entirely is better. Shouldn't take you more than 45 seconds if you practice a bit.

What if the question was: \sqrt{9^2+5^3+10^2+55}+\sqrt{20}

Shalom. I eliminated A, B, and D because they contain the sqrt{20} unsimplified. I am sure that solving it would be better I agree. I am only pointing out that I noticed A, B, and D could possibly be done away with using the process of elimination. The remaining two answers have the sqrt{20} broken down. If the question was \sqrt{9^2+5^3+10^2+55}+\sqrt{20} then I would consider the answer choices with the sqrt{20} simplified.