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Current time:0:00Total duration:3:12

Video transcript

Oh mojo be is 220 centimeters tall he wanted to fill up his pool so that the water level would be as high as he is tall so that the water level I guess would be 220 centimeters tall the water level rose by 6 centimeters each minute and reached the desired height after 20 minutes graph the pools water level in centimeters as a function of time in minutes well they do tell us one interesting thing they say that the that the water level reached the desired height after 20 minutes and we know what the desired height is the desired height is to be as tall as or to be as deep as he is tall or as high as he is tall and that is 20 220 centimeters tall so they're telling us essentially that the water level of the pool after 20 minutes is 220 centimeters so we can plot that so after 20 minutes so we could plot that point right there after 20 minutes we're at 220 centimeters so we would be right there now the other question is where would we put this point we needed another data point in either in order to define a line and so let's see they tell us that the water you might be tempted to say okay maybe the water level was at zero to begin with but they didn't tell us that maybe the what may or may be when he started filling the pool there was already some water in there so we have to be a little bit more careful but they do give us some information the water level rose by 6 centimeters each minute it rose by 6 centimeters each minute so at 20 at 20 minutes we know are at 220 and if we rose 6 centimeters each minute where would we have been where would we have been let's say 10 minutes ago so where we where would we have been at time 10 so every 10 minutes if we're if the water level is rising 6 centimeters a minute it would be rising 60 centimeters every 10 minutes so 10 minutes ago we would be 60 centimeters less so 60 centimeters less than 220 let's see that's 20 centimeters less that's 40 centimeters less that's 60 centimeters less so if you go back in time ten minutes you would go you would be sixty centimeters a shallower or less high and 220 minus 60 is 160 now I think I'm done I think this describes and I'll see if it makes sense this is telling us that at time zero there was hour before he even started filling it there was already a hundred centimeters in his pool and then after 20 minutes he's done and is that consistent with six centimeters a minute well based on this it take it took him 20 minutes took him 20 minutes to get to 220 but that's an incremental 120 to go from 100 200 to go from 100 to 200 20 is 120 more centimeters so in 20 minutes he got 120 centimeters well 120 centimeters divided by 20 minutes is 6 centimeters per minute so this is this is looking good and we got it right