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Multiplying fractions by whole numbers word problem

Lindsay solves a word problem that involves multiplying a fraction by a whole number. 

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Video transcript

- [Voiceover] Rishi spend 3/4 of an hour for two days working on his science project. Kyle spent 1/4 of an hour for six days working on his science project. Who spent more time on his science project? So we wanna know who spent more time, and to do that we need to first know the amount of time Rishi and Kyle each spent on their science projects. So let's start with Rishi, and see what we know about Rishi. Rishi spent 3/4 of an hour for two days, so two times, he spent 3/4 of an hour. Or another way we could say this, is he spent 3/4 of an hour once, plus on a second day he spent another 3/4 of an hour. So 3/4 plus another 3/4 will give us a total of 6/4, or six quarter hours, that Rishi spent on his science project. Now let's look at Kyle. Kyle spent a 1/4 of an hour, so here's Kyle. Kyle spent 1/4 of an hour, but he did this for six days, so six times, he spent 1/4 of an hour. Or we could say that Kyle spent 1/4 of an hour one day, plus 1/4 of an hour a second day, 1/4 of an hour a third day, a fourth day, a fifth day, and then a sixth day he spent 1/4 of an hour. So six times, one, two, three, four, five, six, he spent a quarter, or 1/4 of an hour working on his project. So if we have six 1/4s, then we have a total of 6/4. So Kyle spent 6/4, or six quarter hours. And now back to our question, now that we know how much each of them spent, who spent more time working on his science project? Rishi with 6/4 hours, or Kyle with 6/4 hours? And the answer here, of course, is that these are equal, these are the same. Rishi and Kyle spent the same amount of time, so we could say the same amount of time working on each other their science projects.