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Current time:0:00Total duration:2:29

Video transcript

we are asked which expression can we use to find the missing number in the pattern so pause this video and see if you can try this before we do this together all right now let's try this together and the way I would tackle it is I'll try to see hey can I figure out the pattern between these numbers and then I could try to figure out the missing one so to go from 36 to 45 it looks like I'm increasing by 9 so I add 9 and it looks like to go from 63 to 72 we're adding 9 it's good to make sure that the pattern that you think is happening is happening across all of the numbers that you're seeing and to go from 72 to 81 it looks like you're adding 9 so I'm pretty confident that to go from 45 to this blank number I have to add 9 and we see here indeed choice B is 45 plus 9 that this number here you don't even have to figure out what it is some of you might realize it's 54 but this is just going to be this number plus 9 is going to go in the blank so 45 plus 9 let's do another example so here it's a little bit different it says if the pattern continues what will be the sixth number in the pattern pause this video and try to figure that out alright so first let's figure out the pattern to go from 2 to 6 it looks like we added 4 then we are adding 4 again to go from 6 to 10 then we're adding 4 again to go from 10 to 14 so it seems like we're adding 4 every time and this is the first one two three four numbers in the pattern so the fifth number in the pattern is going to be 14 plus 4 which is going to be 18 and then the sixth number in the pattern is going to be 18 plus 4 which is 22 and that's what they want they want the sixth number in the pattern so 22 is choice D let's do another example here we're told the table below shows the number of laps carly ran around the track each day which rule describes the pattern shown by the number of laps carly ran so like always pause this video and see if you could work on this alright it seems like every time a day goes by the number of laps going up by three so if you want to figure out the next day let's say day six you would add three from day five so the pattern here is to add three