The Windows calculator's programmer mode can verify binary-to-decimal and decimal-to-binary conversions, making it a reliable self-check tool during practice. Calculators are not a substitute for mental math but serve as a useful validation method when drilling number system conversions independently.
Checking Binary/Decimal Work
Some of the worksheets that I've given you have the answers on them, so you can double check to make sure that you're on the right track. But let's say you really want to get this down, which you should, and you wanted to practice making sure that you really have a great concept about how to do this. Well, in that case right there, you can just make up numbers as you go along. But how do you know, if you're trying to figure things out, how do you know that you've come up with the right answer? You can use a calculator to check your work.
Now, the reason why I don't want you to use the calculator for everything else is because if you're going after a certification test, or if you need to know things on the fly, you're not going to be able to have a calculator there to help you out. It's not something that's going to be allowed. What I really want you to do is really get down these concepts so you can come up with the answers very quickly, so you're prepared for it in the real world. For that reason I have not introduced this as an option at this point in time, but it is an option for checking your work and making sure that you're on the right track.
This is the last activity we did, and so what I'm going to do is show you how to check the work. Hopefully I have all the right answers here, but we're going to find out right here in a second.
The first thing that you can do is bring up the calculator on your computer. Most computers have calculators. This is the Windows calculator, and what I'm going to do is switch from its standard — right now I'm going to go to programming. When I go to programming, notice now I have a hexadecimal, a binary; it gives me some extra features that I can work into this.
Now what I want to do is check this 43 and see if it's correct. So I'm going to make sure decimal is selected, I'm going to type in 43, and we can see that the binary equivalent is 00101011. So now I can check to make sure — yep, that lines up, so we're good to go.
How about the next one? I'm going to clear this out, and then the next one is 186. So I can type in 186 and we see that it's 1011010, and we checked that out and that looks correct as well.
Now we need to, let's say, check the other way. Let's say we're going from binary to decimal. How do we do that? What I'm going to do is select binary. Notice that all my numbers are grayed out except for one and zero. So I'm going to clear this out, and what we're going to do is we are going to do this: it's 11011100. So one one zero one one one zero zero. Now we've got that typed in there, and we can see the decimal equivalent is 220. So that worked out and we got the right answer.
I'm going to clear this out once again. The next one is 0110, so I'll do 01100011, and the equivalent in decimal is 99.
I've just checked all my work and things are looking great. So now what you can do is you can just create a bunch of different problems for yourself to solve and then check it with your calculator.
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