Tag Archives: math

Revised GRE Quantitative Practice (FREE)

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No, the site is … ummm … not really designed for aesthetes.  But, hey, free is free.  Thanks WTAMU! While the practice is good, it’s based on the old version of the GRE Quantitative (GRE Math), not the revised GRE quantitative. Your best bet for practice on the GRE math as it looks on the new revised GRE exam can be found at the GRE website. You can download and practice taking a revised GRE exam, which includes GRE math problems.

FYI, be very careful about using third-party resources, such as Kaplan or Princeton Review’s books for their GRE Quantitative problems. They are fine for practice, but be aware Continue reading Revised GRE Quantitative Practice (FREE)

© Cody Blair, All Rights Reserved.

GRE, SAT, and GMAT Practice Nirvana

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More scrumptious FREE practice tests than you can shake a stick at for the GRE, SAT, and GMAT. Regular readers will know that sometimes third-party tests can be sub-par, but a quick perusal of some of the GRE tests shows only very minor errors. Let me know in the comments if you find big problems on any of the other sections. Still, gobs of great practice for the low low price of zero dollars. Thank you, Mathurs! Click the logo to check it out…

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GRE Prep? Must know info for students

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Taking a GRE prep course is really an ideal first step for most students.

You normally start building a house by getting with an architect to plan the building.

Taking a prep course is like talking to an experienced architect first. They can help you make sure that none of your time and effort is wasted.

A GRE prep course can raise a student’s combined score an average of Continue reading GRE Prep? Must know info for students

© Cody Blair, All Rights Reserved.

Estimate percents in your head

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Percents show up a lot in the GRE quantative section. You can really speed yourself up by being able to figure them quickly in your head. That translates to more time on the tough problems.

Can you find 18% of 246 in your head? Here’s a good way to do it. First, some basics. Most of us can quickly figure out what ten percent of a number is. Just move the decimal one space to the left. For example, what’s 10% of 246? Think of it as 246.0. Now just move the decimal one space to the left to get 24.6. More examples,

10% of …

47 is 4.7
1,433 is 143.3
10,012 is 1,001.2

Easy enough. You can do 1% of a number just as easily. Just move the decimal 2 spaces left. So 1% of 246 would be 2.46. We took 246.0 and moved the decimal 2 spaces to the left.

1% of …

47 is .47
1,433 is 14.33
10,012 is 100.12

Finding 5% of a number is easy too. Just find 10% and divide it in half. So,

5% of …

47 is 2.35
1,433 is about 71.5
10,012 is 500.6

Finding 5% may take a little practice before you can do it reliably in your head. Practice for twenty minutes or so, and you’ll have it down.

Now how do we find 18% of something? Just think of 18% as 10% + 5% + 1% + 1% + 1%. Let’s find 18% of 246.

10% of 246 is 24.6
5% is half that 12.3
so 15% … 24.6 + 12.3 is 36.9 (remember that)
1% would be 2.46, but I have three of these so I add 2.46 plus 2.46 … errr … too tough. Let’s just add 2.5 to 2.5 which is close enough. That’s 5. Plus another 2.5 is 7.5.

So 36.9 + 7.5 = 44.4 . Your calculator will return 44.28, so we were pretty close.

Again, it will take some practice to be able to hold the numbers in your head while you add them all up, and some numbers are easier than others, but this method is really powerful. A little practice will pay big dividends!

Here are some to practice on. Remember, this is estimating, so just get pretty close.

  1. 27% of 82
  2. 43% of 118
  3. 98% of 489
  4. 77% of 1500
  5. 12% of 1228

Here are the approximate answers …

  1. 22.14
  2. 51.5
  3. 479
  4. 1155 (I did this one as 75% of 1000 is 750 and half of that would be 75% of 500, so 375. 750 + 375 is 1,125 plus two one percents–30–is 1,155).
  5. 146