Sal uses a picture and repeated addition to solve a multiplication word problem. Created by Sal Khan.
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- How did people get the idea of division(11 votes)
- why so many bottles of soda? #dentist very mad(7 votes)
- they are just representing using bottles of soda. (although if this was a real party I would go to it XD)(6 votes)
- Wait.... I'm confused..... What does 2L means again?(1 vote)
- 2L just means 2 liters. L is short for liters, the basic metric measurement for amounts of fluid, and 2 liters (2L) is a standard size for a large bottle of soda.(4 votes)
So we're asked, "how many liters of soda do we have for the party?" And they give us all of this other information. I encourage you to pause this video and think about which of this information you actually need to answer this first question and then try to answer the question: "How many liters of soda do we have for the party?" So pause now. Let's look at this information: "20 people are coming to the party." This doesn't let us know how many liters we actually have. So we know we can ignore this. "We have purchased 5 bottles of soda for the party." Well, this seems useful - we're going to have 5 bottles of soda. So that's 1... 2... 3.... 4.... and 5 bottles of soda. That's this piece of information right over here. If only we now knew how much soda is in each bottle. "The party will last for 3 hours." This has nothing to do with how many liters of soda we have. "Each bottle has 2 liters of soda." This is interesting. This is 2 liters... this is 2 liters... this is 2 liters... this is 2 liters... and that is 2 liters. If we wanted to figure out the total number of liters of soda we have, We have 5 bottles, and each of them are 2 liters each. So we have 5 times 2 And what is that equal to? 5 times 2 is the same thing as 2 plus 2 plus 2 plus 2 plus 2 You have five 2's added together. Let me write this down... Which is equal to: 2, 4, 6, 8, 10. 5 times 2 is 10. We have 10 liters of soda for the party. We're able to answer it without even looking at this last one. This last one tells us how many bottles of soda we had for the picnic last week. which doesn't seem related at all to our current party.