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Current time:0:00Total duration:2:58

Video transcript

let's say that you're throwing a party and as we all know any party needs a sufficient number of monkeys right now you have 10 monkeys one two three four five six seven eight nine ten but you would like to have 18 monkeys so how many more monkeys do you need in order to have 18 monkeys and I encourage you to pause the video and think about it on your own before I work through it so remember the goal here was is to get to the goal here right this way the goal here is to get to 18 18 monkeys now what do we know about the number 18 well the number 18 you have this one right over here in the tens place so that literally represents 110 and then this eight represents eight ones so plus eight ones and that's the same thing as saying 110 110 that's just a 10 right over there and eight ones that's just eight so 18 is the same thing as 10 plus 8 so if we start with 10 monkeys which is how many we have started with how many more do we need to get to 18 well if you start at 10 you need 8 more to get to 18 and we can verify that visually if we like so let's so let's see let me copy and paste one of these monkeys copy so this is 10 so now let's get to 18 so 11 12 12 13 14 15 16 17 and 18 and 18 so how many more did we add well once again we started we started with this 10 right over here and let me box them off we started with these 10 monkeys so that's one group of 10 right over there so we started with the 10 and then we added eight more monkeys 1 2 3 4 5 6 7 8 1 2 3 4 5 6 7 8 so we started with 10 we added 8 more monkeys we added 8 more monkeys to get to get to 18 and once again how did we first think about that well 18 is 1 10 plus 8 ones or 10 plus 8