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Current time:0:00Total duration:3:45

CC Math: 3.MD.B.3

- [Voiceover] Maria has
70 pages in her notebook. She made a graph of the kinds of writing on all the pages she has used so far. How many pages are left
in Maria's notebook? Down here we have a picture
graph, or pictograph, showing all the pages Maria's
used so far in her notebook, but we're asked how many pages are left in Maria's notebook. To find that out, we need to know how many she started with, which
it tells us right here. Her notebook started with 70 pages, and then if we take away
the ones she's used so far. If we take away however
many pages she's used so far that will tell us how many are left in her notebook. The question here is how
many has she used so far? We don't know exactly, but
we have this picture graph that will help us find that answer. Super important on the
picture graph first, is right here, it tells
us that each of these pieces of paper represents
two pages in Maria's notebook. For poems, she wrote on two
pages and another two pages, or she wrote on a total of four pages about poems. She did reports on two,
four, six, eight, ten pages. She wrote stories, she
wrote a lot of stories. She wrote stories on
two, four, six, eight, 10, 12, 14 pages of stories. She wrote letters on two,
four, six, eight pages. And finally, she journaled on two, four, six, eight, 10, 12 pages. This here, this is the total
pages she's used so far. If we combine all of
these, the four for poems, the 10 for reports, and so on, this will tell us how many
pages she's used so far. Then we can substitute that in right here, and we can say 70 she started with, take away what she used so far, and we'll get our final solution for the pages left in her notebook. Let's find this total,
there's four pages for poems, plus 10 pages for reports, 14 on stories, eight more pages to write letters, and 12 pages to journal. If we add these, I'll start with the ones, two ones plus eight ones is 10 ones. 10 ones plus four ones is 14. Plus zero more is still 14 ones. Plus four more is 18 ones. Plus, now let's add our 10s. One 10 plus another 10 is two 10s, or 20. Plus one more 10 is three 10s, or 30. She's 18 ones plus three 10s, so 18 plus 30 pages, which is a total of 48 pages. She's used 48 pages so far. If we take those 48 away from 70, we'll know how many pages are left. One way we could do this, is we can think of it as counting up. We can say there's 48 pages
used, let's count up to 70 to see how many more pages
there still are in the notebook. If we count up from 48 to 50,
that's two more pages she has, and then from 50 to 70 is 20,
that's 20 more pages she has, so she has a total of 22 more pages left in her notebook.