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Current time:0:00Total duration:3:46

Video transcript

so we have three folks Jenna Sarah and Bill and they're keeping track of their weight and their in particular they're keeping their track of the keeping track of their weight over a month and right over here we have their weight change over the month so if you take their ending weight and from that you subtract their starting weight so let me just write that that's your end weight - your starting weight that's going to be your change in weight over that month and so we have the change in weights here so Jenna's change in weight is negative three pounds which means that she lost weight sarah's change in weight is positive two and a half pounds which means she gained two and a half pounds and then bills weight or a change in weight I should say is positive four pounds which means he gained four pounds over the month so given that let's answer some questions who lost the most weight who had the largest change in weight and who had the smallest change in weight and I encourage you to pause the video and try to work through it on your own well let's just let's just let's just plot all of these on an on a on a number line here to help us think through it although you know some of you might already have an answer here so Jenna's weight change is negative three pounds so that's Jenna right over there I'll say J for Jenna Sara's weight change and she had a weight gain is two and a half pounds so that's right over there positive two and a half pounds for Sara and then finally bill gained four pounds so that is bill right over there now let's answer the question who lost the most so when we talk about lost where we care about directions we said hey who moved who moved most to the left of zero well serán buildin moved left to left to zero at all they gained weight that's why I did it to the right of zero Jenna is the only person who lost anything so the person who lost the most is Jenna now who had the largest change and if we think about the largest change one way to think about is who is the farthest away from zero so one way to think about it is which of these is the largest absolute value well the absolute value here the absolute value of negative three is and let maybe let's see we could just call this the absolute change absolute change is just going to be the absolute value absolute value of negative 3 is positive 3 absolute value of 2.5 is 2.5 absolute value let me make this a little bit clearer absolute value of 4 well is just equal to 4 so who had the largest absolute change well bill had the largest absolute change and then second place was actually Jenna she lost weight but she had a pretty big change she had a three pound change although it was a three pound loss bills was a four pound gain but the largest change is definitely bill now who had the least change well another way to think about this is the least absolute change who changed the least from zero well if you look at here Sarah had the smallest absolute change Jenna lost weight so the the weight change of Jana she has negative 3 versus Sarah's positive 2.5 but if we talk about who had the least change from zero if your weight change was zero that means you didn't gain or lose weight from the beginning of the month to the end of the month so who had the least change well that's the least absolute change well we see that right over here 2.5 is less than 3 or 4 so the least change is is Sarah and we're done