Even though there are cases where the online calculator will help you, it’s best to minimize its use.
As I am wont to offer boring stories, I can’t help but share the following:
I was working with a high school senior who was prepping for the ACT. A bright student doing well in her calculus class, she already had earned a score of about 32 on the ACT, and wanted to boost that up a few points (out of 36 possible). I suggested a quick and easy way to reach her goal: noticing that she was using her calculator for virtually every computation, I suggested that cutting back on her use of her calculator would save time and energy, enough by itself to boost her score. Alas, she did not receive this well, so I asked her what is 8 + 5. She didn't know. And she pushed back on the idea of memorizing the basic math facts.
Interestingly, the older students, those preparing for the GRE, tend to be more open to this easy fix.
Let’s do the math on this issue. There are 40 quantitative questions that are scored for the GRE. If you can easily slice off 10 seconds from each question on average, that’s a total of 400 seconds saved. Quick….how many minutes is that? Yes, almost 7! Enough time to get a few more questions correct.
Besides saving time, there are additional benefits to using what is called “mental math” but I refer to as “air math” or “visual math” instead—reducing cognitive load and “attention switching.”
Reducing Cognitive Load (Brain Power)
How much problem-solving information can you hold in your head at a time? This varies from person to person, but it’s not infinite. The more basic computations you can make automatic, the easier it becomes to use in a problem. Not only does it save time and energy, but it also enables you to focus your attention on the reasoning aspects of a question. (Example questions in a future post.) If you can subtract 25-16 using air math, it probably wouldn’t take more than 5 seconds, and use very little brain power. Now imagine turning your attention to bringing up the online calculator, typing in “25-16” and hitting Enter, closing the calculator, and finally turning your attention back to your scratch paper. About 9 seconds! There is also a risk of miss-entering a value, which can be greater than if you had used visual math.
Limitations of the GRE Online Calculator
The online calculator provided on the exam can only support 8 digits! This prevents you from brute-forcing some of the questions. In these cases they are testing your ability to use quantitative concepts to solve the problem. (Example questions coming soon.)
Practice Using a Simulation of the GRE Calculator Before the Actual Exam
There are a few apps available that you can use during your prep for the exam. This is especially important if you are used to using a scientific calculator or a graphing calculator. The switch-over does take some mental and muscle response re-programming. You can get the app here.
Here is how I became aware of this issue:
For the last few years I have used “FreeCell” games (a form of solitaire) on the computer to decompress after a hard day’s work. And I recently downloaded a phone app of this.
Waiting at the dentist’s office, and trying to distract myself from contemplating an impending root canal, I opened FreeCell on my phone and began to play. I noticed immediately that, even though the strategy was exactly the same as the large-screen version, there was a definite visual recognition learning curve that was slowing me down.
You don’t want to lose exam minutes getting in gear with a “more basic” calculator than you are used to.