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PDF archive of questions from GMATQuantum blog

The pdf file above contains all of the questions published in the GMATQuantum blog. Please download the file and then open it in Adobe Acrobat Reader for all of its features to work properly.

GMAT Strategies: Articles from GMATQuantum Blog


GMAT Problem Solving 87: Circle surrounded by circles

Try this GMAT problem solving question on a circle surrounded by four circles that are tangent to each other.

In the figure shown below, a circle of radius \(1\) is surrounded by \(4\) circles of radius \(r\). What is \(r\) ?
  1. \(\quad \sqrt{2}\)

  2. \(\quad 1+\sqrt{2}\)

  3. \(\quad \sqrt{6}\)

  4. \(\quad 3\)

  5. \(\quad 2+\sqrt{2}\)


GMAT Problem Solving 86: Triple Venn diagram problem

Try this GMAT problem solving question on triple Venn diagrams. There is no need to memorize the formula for triple Venn diagram problems because there are too many variations on the GMAT and it is best to have a general approach in place.

Each of the \(100\) students in a certain summer camp can either sing, dance, or act. Some students have more than one talent, but no student has all three talents. There are \(42\) students who cannot sing, \(65\) students who cannot dance, and \(29\) students who cannot act. How many students have two of these talents?
  1. \(\quad 16\)

  2. \(\quad 25\)

  3. \(\quad 36\)

  4. \(\quad 49\)

  5. \(\quad 64\)


Official Guide GMAT 2018: Offline access to video explanations on YouTube

I have released YouTube video playlists for all the quantitative reasoning questions in the Official Guide to GMAT 2018.

YouTube Playlist: Problem Solving 2018 Official GMAT Guide

YouTube Playlist: Data Sufficiency 2018 Official GMAT Guide

Of course, students can also access these playlists on this website at the following link: Official GMAT 2018 Videos.

The reason I released the YouTube playlists is to give students an option to watch the videos in offline mode. The following is the list of countries where YouTube is available in offline mode: Algeria, Egypt, Ghana, India, Indonesia, Jordan, Kenya, Libya, Malaysia, Nigeria, Pakistan, Philippines, South Africa, Thailand, Vietnam, Yemen. This will allow students to download the entire set of video explanations to the questions in the official GMAT guide. This means that students can watch these videos when they are studying in a cafe or traveling to and from work. Of course, the download will still use data bandwidth initially.

If you need to access the videos in the US, then you will need to be a YouTube Red member, which costs $10/month in the US, and is also available in the following countries: Australia, Korea, Mexico, New Zealand.