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# Measuring lengths (cm, m)

CCSS.Math:

## Video transcript

which shows the length of the rectangle measured correctly all right so here we have this green rectangle and let's see how did we measure it we have one centimeter right over here and then we put another centimeter right over here and they say two real two rulers measure the rectangle side to side well this makes sense because we can say look if from here to here from the beginning of the rectangle to the middle is one centimeter and then it's another centimeter that gets us to the other side to the right side then we know that this is going to be two centimeters long one and two so I'm pretty sure this is measured correctly but let's just make sure that the other two don't really measure the rectangle correctly so this one right over here you have one centimeter and another centimeter but you're leaving a gap right over here and you can't measure you can't leave a gap here you want to measure what this distance is and you notice that this ends to the right of the right of the rectangle so this isn't a good way of measuring it and this way you're not going all the way the entire length of the rectangle so this you're coming up short you need to measure the entire length you just start on the left side which they did but you need to go all the way without any gaps and without overlapping the rulers in any way to get to this side so this isn't right either so let's keep doing these which shows the length of the eraser measured correctly so this one well once again there's some weirdness over here I don't even know what's happening but the entire ruler isn't even getting to the entire length of this rectangle so this isn't measured correctly and they say two rulers measure the eraser and overlap oh I see this is kind of the rulers a little bit transparent so this one is overlapping with the one underneath so you definitely don't want to do that you want to put them right next to each other without a gap and you want to get all the way to the edge of this rectangle so this one you have a gap and you're actually going you're actually going beyond the edge of the rectangle so that's not good here you have no overlap and no gap right over here they're just right next to each other and we're starting at the left side of this rectangle and we're going exactly to the right side we're not over overstepping it or we're not under doing it so this is going to be right this is a lot of fun let's do okay this is interesting what is the length of the floor of the bank in meters this is a picture of a bank I guess this is the big money in the bank those are big dollar bills and those are big coins drag the ruler to make the measurement and this is in meters so I can click on this and then I can put it remember I want to I don't want to do this this would be wrong because I want to start measuring right at the edge right at the edge of the bank so I want to do it like that and I see okay the length of the bank well how much is that well you see this right wall right over here it's right at 4 right at 4 meters so this is going to be 4 meters long let's do another one what is the length of Maria's backyard and meters drag the ruler to make the measurement so once again you don't want to do something like this where you're starting to measure before the garden even starts you're starting to measure too late you want to measure right at the edge right over there so that's where the garden starts so that's where your ruler should start measuring 1 2 3 4 5 6 7 8 looks pretty close let's see it looks pretty close to 8 8 meters right over here so yeah this this length of this is 8 meters looks pretty close I'll say 8 all right let's do one more of these what is the length of the tray of cookies in centimeters and when they say length they mean the length actually means the longest dimension if you have a width and a length and so the longest dimension of a tray of cookies is going to be this this side right over here you don't want to measure you don't want to measure that side up there that would not that would not be the length the length if people don't tell you otherwise it's the longest dimension so we want to measure so we want to measure let me make sure I don't lose my ruler we want to measure we want to measure along the top or along the bottom and we see that it is once again we don't want to do this that would be starting the ruler too far to the left and you don't want to do this starting the ruler too far to the right you want to put it right at the edge right over there my ruler isn't perfect straight and we see that this cookie tray is it is right at about eight centimeters eight centimeters and we're done