About this video
A short ratio word problem about Angel's ice cream shop, which sells ice cream by the scoop and by the pint. Of the 310 customers who bought scoops, 27 also bought pints, so the fraction is 27 over 310. The key step is choosing the group named in the question, scoop buyers, as the denominator.
You'll be able to
- identify the group that defines the denominator in a fraction word problem
- read counts from a table and build a fraction
- choose the matching answer from a fraction
Key words
- Fraction
- A part over a whole, written as numerator over denominator.
- Denominator
- The total group the question starts from.
- Numerator
- The count within that group that meets the extra condition.
- Subset
- A group inside a larger group, such as scoop buyers who also bought pints.
Transcript
- [Instructor] Angel's ice cream shop sells ice cream by the scoop and by the pint. The table above shows the purchases made by his customers last weekend. Of the customers who bought scoops, what fraction also bought pints? So pause this video and see if you can figure this out on your own.
All right, now let's look at this. So "of the customers who bought scoops." So I can do that as the denominator of a fraction. So customers, customers buying scoops. They are saying, "what fraction also bought pints?" So bought, bought pints. So we're looking at the customers that bought the scoops.
So bought scoops is right over here. And we know that there's a total of 310 that bought scoops. So this is going to be equal to 310 as our denominator and then of them, which, how many bought pints? Well, we could see that right over here, 27 bought pints. So 27 over 310, which is this choice right over here.
And we're done.
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