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Mister brooker back here talking about commutative and associative. I'm sorry, commutative and associative property. So if you look on your books, on page 474, there's a little bit of a review there. Okay. So these only work when we're talking about what two kinds of math. It's plus and multiplying. Third identity is the third property is identity. So you add a little homework assignment, kind of quizzes you to think about, hey, if I'm adding and subtracting, when are they the same? Excuse me. I'm adding and multiplying. How do these numbers stay the same? And when are they different? Okay? So identity property, you look at page 374 for help is when we times by one or add zero. Okay? These do not work when I divide. Yes, 46 and 15 is the same as 15 and 46. That's called commutative. And 13 times one. 13 times one and one are no. So hopefully you got those right. Look at 22. Anita's mother hosted a party. The table shows the cost associative property to write two equivalent expressions. So when I see associative, I'm adding around multiplying and it doesn't matter what numbers are in the parentheses because they're going to equal the same. So if she's having a party, she needs hot dogs cake and drinks, it doesn't matter if she buys cake and drinks. And then hot dogs is gonna be the same as if she bought hot dogs and drinks and cake. Now, real quick, I like to use associative property because it's easier to say, all right, here's 18 plus 24. That's a little bit harder math. Than saying, hey, what is 24 and 6? That's 30, 30 plus 12. Which one would you rather add up? 18 to 24 or 30 and 12, both of them are going to equal 42, which that should be your answer. Number 23 says Ellie sold 37 necklaces for $20 apiece. So that's multiplication. I know this already. She made a lot of money. She's going to donate half of the money to charity. Okay? So we got to use commutative property to figure out how much she's going to donate. So I've got 37 times by 20. Okay? And then I'm also timing this by a half. Okay, so this is a different way of saying divided by two as I times it by a half. Okay? So it doesn't matter if my parentheses are anywhere, right? I'm going to get the same answer. It's just easier to take half of 20. What is half of 20? Half of 20 is ten and ten times 37 is $370. It's a lot of money donated. Hopefully that's what your answer looks like. But think about it again. I could take 20 times 37, and I'm going to get 740, then when I divide 740 by two, or I'm sorry, yeah, I'd get three 70. Okay, so that's commutative and commutative and associative property. Here's one of the ones I'm going to grade. I'm not going to answer all these. I've got an X and I've got 6s. So whatever this X is, we don't know and we don't have to know. We know that if we add 6 to it, it's going to be the same no matter how it's ordered. 25. Okay, I've got four plus B I've got a zero and a four. It's my like terms. My variables are always by themselves four plus B your answer for 26. And you can look at 27 here. 20 times 6 times Y is going to be the same as a 120 times Y and I don't know Y equals. I don't need to have to know what Y equals. 28 is another one. I'm going to grade circle 28 and look at 29. If I got W times 12 times three, that's the same as having 36 times by W flip your paper over. Number 30 is one that I want to grade, but let me help you. Which of the following shows total desks, okay? There's a lot of desks here. This would be times by, this would be times by, and this would be times why I don't need Yorktown though, okay? Because it's asking for Medina and Monroe. So before I give you the answer, how many 12 times 25s do I have? Okay, think about that 12 times 25. I already eliminated a couple of these problems for you. And number 31, which of the following expressions is equivalent to three plus four plus 7. Different numbers. Not equivalent. It might be the right answer here, but when I add it up in my head it's not. Adding, not multiplying. So the answer is right here. It doesn't matter if I change the order of the parentheses. Number 32. What property is this? It is D, the identity property of multiplication. We didn't go deep into identity properties. And number 33, I'm going to let you do this by yourself. Jerry deposits $2 into the savings account. Every week for 6 days. Okay, so is that multiplying or adding? So now we're going to write two expressions that could be find out how much you saved after 6 weeks. First off, you're going to need to know how many days are in a week, which is 7. How much money he donated, which is two, how many weeks you did it, which is 6. I'm going to stop right there. Expanded form is three times 5, 37 times by one, and oh, no, that's not right. Ten plus 5, 30 plus 7. I'm going to grade 36. Okay, lakeisha has $10 bills and $1 bills in her wallet. She used 7 bills to buy $43 shoes. How much of each type of bill did she spend? How many tens and how many ones it's going to be real similar to how you did these problems up here. In fact, I'm going to grade 37, one, two, three. Four, 5, and let's grade 38. Margot has three dimes and Justin has 5 dimes. They put their money into a donation box. What is the value of their money? My son's been doing that in kindergarten. I'm hoping, hoping you guys can tell me how much money that is. All right, so now we're going to move on to distributive property, mister brooker is going to be talking a little bit about this in class, but I want to give you guys a sample problem to think about. Okay? So if three friends go to a movie, okay? And all three friends buy popcorn, which is like $6. And all three friends bought movie tickets, which are $8. How could you write these numbers out? That's kind of what we're thinking about. How much money got spent at the theater, that's how we're going to use distributive property and we'll show you more in class. Thanks guys.