About this video
Jess takes 2 minutes to prepare each sample bag and needs 1,200 bags. Alone that is 2,400 minutes, but with seven friends there are eight people, so it takes 2,400 / 8 = 300 minutes, which is 5 hours.
You'll be able to
- find total time by multiplying time per item by the number of items.
- count all the workers, including the person who asks for help.
- convert minutes to hours by dividing by 60.
Key words
- rate
- How much of something happens per unit, like 2 minutes per bag.
- convert
- Change a measurement into different units, like minutes into hours.
Transcript
Jess recently started a business producing cosmetic products made from natural ingredients. She wants to advertise her products by distributing bags of samples in her neighborhood. She calculated that it takes her two minutes to prepare each bag. How many hours-- they give us minutes here, now they want hours-- how many hours will it take to prepare 1,200 bags of samples if she asks seven friends to help her with her work?
So the one thing we could think about is, how long would it take her to do it by herself? So it takes her, by herself, two minutes per bag. And then we have 1,200 bags, not 12 bags, 1,200 bags which means it's going to take her two minutes for each of the 1,200 bags.
Well that's 2 times 1,200 is 2,400 minutes. Now that's if she was just working on it by herself, but she's got seven friends. And we can assume that they would all take about two minutes to prepare each bag. Now this is a little bit tricky because you might want to divide this by 7 saying, hey, we're going to have seven times as many people.
But you remember, she asks seven friends so there's actually eight people involved. There's Jess and her seven friends. So it's actually going to be eight times faster than if Jess did it by herself. This is if she only had one person. If you're going to have eight people, you are going to take eight times less time.
So with eight people, it's going to be 2,400 divided by 8 is 300 minutes. And we're almost done, except for the fact that they asked for our answer in terms of hours. So 300 minutes is how many hours? Well you have 60 minutes per hour so you could say 300 minutes-- I'll just write min for short-- divided by 60 minutes per hour gives us 300 divided by 60 is 5 hours.
So it will take Jess and her seven friends, a total of eight people, five hours to prepare all of her sample bags.
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