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Current time:0:00Total duration:5:50
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Video transcript

Domonique drew a 72 centimeter line on the playground with blue chalk so the line that she drew maybe it looks something like that and that is 72 centimeters 72 centimeters long so from there to there is 72 centimeters and another line with pink chalk that is so let's do this with pink chalk another line with pink chalk that is 14 centimeters longer than the blue line so let me draw the other line so the other line whoops the other line is going to be 14 centimeters longer so maybe it looks something like that so it's definitely going to be longer and it's 14 centimeters longer so if we go from here to here that's going to be the same so maybe we make it the same length this is going to be the 72 centimeters that's 72 centimeters but it's also another 14 centimeters so it's going to be 14 centimeters longer so how long is a pink chalk line the Domonique drew well you just add the 72 plus 14 so 72 plus 14 is equal to 2 ones plus four ones is six ones seven 10s plus one 10 is eight 10s so this longer line here is going to be 86 86 centimeters let's do another one so we're told a cable on the Golden Gate Bridge is 33 meters long another cable is 13 meters longer than the first cable let me do this in a different color color is 13 meters longer than the first cable how long would the cables be if lined up end to end so they're not just saying how long is the longer one like they did in the last example they want to know how long is are the cables if you line them up end to end so this first cable is 33 meters we draw it this way so the first cable is 33 meters long 33 and actually why don't I draw it why don't I draw it this way because this is what the cables would actually look like so this cable is 33 33 meters long another cable is 13 meters longer than the first cable so this other cable right over here is 13 meters longer so this cable right here is 13 meters longer so what's the length of this cable well it's going to be the length of the first one 33 plus 13 is 13 meters longer plus 13 that gets us three plus three is six three plus one is four this one over here is going to be 46 meters now they didn't just ask how long is the second cable which is 46 meters they're asking how long would the cables be if we line them up end to end so if we line to the 33 meter one so if we lined up the 33 meter one and then right next to that we right next to that put the 46 meter one so if we did something like that well we know that this one over here is 33 meters and the next one is 46 meters so we would have to add 33 plus 46 to figure out how long they would be end to end and what is that going to be so we say 33 plus 46 plus 46 three ones plus six ones is nine ones three tens plus four tens is 79 three tens plus four tens is seven tens so it's going to be 79 meters if we line them up and to end let's do one more Reynaldo has a 36 centimeter scarf so he has a 36 centimeter scarf he decides to cut out part of the scarf so it is now only 19 centimeters how many centimeters did Reynaldo cut off of his scarf so let's draw his scarf so it was a 36 centimeter scarf so it might have looked something like this so this was his scarf before if I stretch it all out and it is 36 centimeters 36 centimeters long and but he cuts part of his scarf so it's only 19 centimeters long so now it is only 19 centimeters so it's going to after he cut it it's going to look something like this it's actually maybe I'll actually I'll draw it in green again so after he cuts it his scarf is going to look something like this it's going to look something like this where now it's only 19 centimeters 19 centimeters so how much did he cut off well what he cut off is going to be the difference between 36 and 19 he would have cut to cut off he would have to cut off all of this right over here in order to get it down to 19 so how much would he have to cut off well this right over here is going to be 36 minus 19 it's the difference between 36 and 19 so let's figure out let's figure out what that is it's going to be 36 minus 19 so let's see if we we have six ones we want to take away nine one so let's do a little bit of regrouping let's take one of our tens here so instead of three tens we have two tens and then if we add that 10 to the ones place instead of six ones we're going to have 16 ones 16 minus 9 is 7 two tens minus 1/10 is 1/10 so he would have had to cut off 17 centimeters of his scarf if he started with 36 centimeters he cuts off 17 centimeters he's going to be left with 19 centimeters and you could you could do that the other way around you could start with 36 you could cut 17 and see what you end up with you're going to see that you end up with 19