HOLY $@#& I FINALLY UNDERSTAND RATES!!

Not sure why, but sometimes I have a mental block at understanding a concept. Different methods of learning work for different types of math problems. For instance, I didn't quite get combinations completely even though I spent 10 hours a day for 5 days going over and over it. And then, krusta80 (user name of a friendly beatthegmat.com user) explained a complicated combination problem with constraints to me, and all of a sudden - something clicked, and now I get it.

Similarly, I had been struggling with rates until I read the rate section in the Barron's GMAT Workbook. Easier and even most of the medium questions I could figure out, but complicated rates with vehicles traveling toward or away from each other, etc - I just couldn't quite conceptualize how (or even what??) to set up.

If you are having problems with complicated rates, buy the Barron's GMAT Math Workbook. I'm a Princeton Review 18 hour instructional veteran myself, I've done the GMAT Pill (which also happens to be great btw) but it didn't quite click until I read the Barron's.

So if you're having rate issues too, I recommend the following:

1. Princeton Review Math Workout book to get the basics of rates. I don't find their rate problems to be hard enough by comparison to true 600 and 700 level GMAT rate questions. But it gets you started.

2. Do the Quant from the GMAT Pill. His methods are great - but if you don't have a solid understanding behind you, you will get confused. That's ok. Just plow through it and let your mind go numb and break in half. By the time you're done with this, your brain should hurt and you'll go to sleep depressed that you still can't do it. That's fine - it's part of the process.

3. Then - do the rate section from the Barron's GMAT Math Workbook. Start at the beginning of the section (section 4), going through all the simpler stuff you already know. No, it is not a waste of time. Once you get to the first couple of practice problems in section 4.2 a giant light bulb inside your brain will go CLICK and things will clear up for you.

4. Complete the entire section 4 from the Barron's GMAT Math Workbook. Do all the practice problems.

5. Do as many rate/work/speed problems from the official guide as you can over the next 48 hours.

6. Bask in your own glory, as you are now a rate/work/speed master.

Also - krusta80 sent me an alternative average speed formula which totally rocks.

2(R1) x R2 / (R1 + R2) = Average Speed/Rate/Work

In words: two times Rate1 multiplied by Rate2 divided by Rate1 plus Rate 2.

This is of course in addition to the one we all know, which is a manipulation of TotalRate x TotalTime = TotalDistance (or total work) which in shortened form looks like Rt = Dt/Tt

DON'T FORGET TO CONSTANTLY MAKE FLASH CARDS!!

That's it! Back to studying.

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