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CCSS.Math:

what we have here are pictures of running pigs and we could try to figure out how many running pigs there are by just counting the pigs but we're going to start building some new muscles and this muscle is going to involve hey if we group the pigs into equal groupings can that help us figure out how many pigs there are and you can see that I have groupings of seven each of these groups are seven running pigs so how many total groups do I have well I have one two three groups of seven running pigs each three equal groups so if I said what's the total number of running pigs that I'm dealing with well I have three sevens three groups of seven and so that's the same thing as 7 plus seven plus seven and if you wanted to figure out what that is you could skip count if we skip count by seven we go 7 then 14 then 21 and so three sevens which is seven plus seven plus seven is twenty-one so there's twenty-one pigs here and you can verify on your own that if you count this you will indeed see twenty-one pigs let's do another example so here I'm looking at a picture of a bunch of blue seals not something that you are likely to see in the wild and these blue seals have once again been grouped let's see how many groups there are there one two three four five six seven groups and how many are in each group well we could see that they're all groups of 1 2 3 4 5 they're equal groups so what are we dealing with well we're dealing with seven groups of five so I could write seven groups of five I could write seven fives I could write 5 plus 5 Plus 5 Plus 5 Plus 5 Plus 5 plus 5 so that is 7 fives there and if I wanted to figure out where that is I could skip count I could skip count 7 5 so that would be 5 10 15 20 25 30 35 so if I were to have all these fives up 5 Plus 5 is 10 another five you get to 15 out of their five 20 add another five twenty-five as another five thirty add another five thirty five which is exactly what you see there so we're starting to see that sometimes grouping things can help us appreciate how many things there are there and I know what some of y'all are thinking well hey couldn't I just count things well you could but what if you had a hundred groups of five well then it'd take a little bit more time to count but the techniques that we're building will help you one day be able to think about those things quite easily