About this video
Ebuka eats 8% of a new cereal box per bowl, so after one bowl 92% remains. Dividing the remaining 92% by 8% gives 11.5 more bowls. The video also shows that using a made-up quantity such as 100 units gives the same answer, because the calculation depends on proportions rather than the specific unit.
You'll be able to
- find the remaining share of a quantity after a percentage is removed
- divide a remaining amount by a per-serving amount to count servings
- check a percent problem by substituting a concrete unit
Key words
- Percent of the original
- A share measured against the full starting amount, here the whole new box.
- Remaining amount
- What is left after the first serving is removed from the original 100%.
- Servings
- The number of equal portions that can be taken from the remaining amount.
- Unit substitution
- Replacing a percentage with a concrete quantity, such as 100 units, to make a problem easier to see.
Transcript
- [Instructor] We're told today, Ebuka opened a new cereal box. He ate a bowl of the cereal, which was 8% of the cereal in the entire box. Approximately how many more bowls of cereal can Ebuka expect to get from this box if he continues to eat the same amount of cereal in each bowl?
All right, pause this video and see if you can answer this on your own. There are several ways that you could approach this. You could say, all right, the box starts off with 100% of the cereal. Then in that first bowl, he eats 8%, and so you're left with 92% of the original new box amount of cereal, and then every time, he's going to eat 8% of the original amount that was in the box.
So if now we have 92% of the original amount in the box, and at every serving, he's going to eat 8% of it, we just divide by 8% to figure out how many servings he'd have. And so 92 divided by eight. See, eight times 11 is 88, and then you have four more, so this is going to be 11 and a half bowls, and that is this choice right over here.
If the percent is confusing, you could say, all right, let's just imagine that there were, I don't know, 100, pick a unit, in the original box. Then every serving, he eats eight, and so he's left with 92 and then if every serving, he's eating eight, 92 divided by eight is 11.5.
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