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Video transcript

a volunteer group is planting trees at five different parks they plan to 90 trees at each Park how many trees did the plant did the group plant at all so here's what we know we know that this group went to five different parts very kind of them and plan to ninety trees at each of those parks so if we want to know the total amount we could do a couple things we could say they plan to 90 trees a park one plus ninety Moore Park two plus you see where this is going 90 Moore Park three plus ninety Moore Park four and finally ninety Moore Park five so one way to solve this would be to add all of those 90s we could do it it'll take a while but we could get there or we could say that the group plan to ninety trees five times five times they planted ninety trees so ninety times five let's solve both of these either great ways to get to our solution but maybe solving both of them will help us see if we liked one way better if one felt simpler for us so ninety number ninety we can think of as nine tens I'll write that up there and that'll help us add nine tens plus nine tens of eighteen tens plus nine more tens is twenty seven tens plus nine more tens is thirty six tens and the last nine tens gets us forty five tens or four hundred fifty that zero is because we're talking about tens forty five tens or four hundred fifty so the group planted four hundred and fifty trees now let's try the multiplication way and see how that goes so again ninety ten ninety we can think of as nine tens times five so if you have nine tens five times you have forty five tens and forty five tens is again four hundred fifty get that zero on the end both ways we see this is a very generous group they planted four hundred and 50 trees either way we could add or we could multiply for me the multiplication gets me there faster I like the multiplication way but either way we can see 90 trees at five parks is 450 total trees