About this video
To convert 37 centimeters to meters, the video uses the fact that centi means 1/100, so 37 cm is 37/100 of a meter, or 0.37 m. It also shows a reality check (meters are bigger, so the number gets smaller) and that dividing by 100 moves the decimal point two places to the left.
You'll be able to
- explain that centi means one hundredth.
- convert centimeters to meters by dividing by 100.
- check whether a converted answer should be bigger or smaller.
Key words
- centi
- A prefix meaning one hundredth (1/100), so a centimeter is 1/100 of a meter.
- decimeter
- One tenth (1/10) of a meter.
- reality check
- Asking whether your answer makes sense, like whether it should be bigger or smaller.
- decimal point
- The dot that separates whole numbers from parts of a whole, like in 0.37.
Transcript
Convert 37 centimeters to meters. Let me write this over. 37, and I'll write centi in a different color to emphasize the prefix. 37 centimeters, and we want to convert it to meters. So we really just have to remind ourselves what the prefix centi means. Centi literally means 1/100th, or one hundredth of a meter.
So this is really saying 37 hundredth meters, so let's write it that way. This is literally 37/100 of a meter. So 1/100 meters. These are equivalent statements. So what are 37/100 of a meter? Well, that's going to be 37/100 of a meter, which can be rewritten as, if you wanted to write it as a decimal, that's 0.
you could view it as 3/10 and 7/100, or 37/100. So 0.37, 0.37 meters. Another way that you could have thought about this is look, I'm going to go from centimeters to meters. I have 100. I need 100 centimeters to get to one meter, so I'm going to have to divide by 100 in order to figure out how many meters I have.
And you should always do a reality check. If I convert centimeters to meters, should I get a larger number or a smaller number? Well, however many centimeters I have, I'm going to have a fewer number of meters. Meters is a larger unit. So you should have a smaller value here, and it should be a smaller value by a factor of 100.
So you literally could have started off with 37 centimeters. Let me write it this way, 37 centimeters. And actually, let's go through a couple of the units right over here. Now, if you wanted to turn it to decimeters, so this is 1/100. Decimeters, one over 1/10.
So you would divide. This would be 3.7 decimeters. Let me write this as 3.7 decimeters. And a decimeter is 1/10 of a meter, so you would divide by 10 again. So this is 0.37 meters. So one way to think about it is to go from centimeters to meters, you're going to divide by 100.
Dividing by 100, you would move the decimal space over to the left two times. Doing it once divides by 10. Doing it twice divides by 100. So you get to 0.37 meters.
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