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Basic ratios

Sal writes ratios from images, contexts, and tables.

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  • piceratops tree style avatar for user Timothy
    In real life I never used ratios, so my question is are ratios very useful?
    (15 votes)
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  • aqualine ultimate style avatar for user Dude
    "This is strangely fun" XD
    (10 votes)
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  • duskpin tree style avatar for user farha shemi
    what does it really mean when Sal says for every blank there is blank
    (8 votes)
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    • blobby green style avatar for user Jordyn
      it is just different way of say for example 3 to 4 so you could also do 3:4 or for every 3 there is 4. So it i just a different way to specify the problem. there are 3 different ways you can say or write it.
      (3 votes)
  • blobby green style avatar for user Emilyoct3
    Do u have videos like this in Spanish my school does math in Spanish and the vocabulary is different making it a lot harder ?
    (8 votes)
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  • blobby green style avatar for user 201802491
    me joining just to read comments a lot but this is just SAD comments...
    (8 votes)
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  • scuttlebug green style avatar for user JacobS
    If you see this upvote it XD
    (8 votes)
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  • leafers tree style avatar for user Kevin. X
    Can a rate be converted into a ratio, and vice versa?
    (5 votes)
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    • duskpin ultimate style avatar for user Mysterious
      Yeah, you can convert ratios into rates and back, although going back is less useful. It is called unit rates. Unit rates, which are a ratio in which the denominator's unit is one, allow us to compare. To calculate unit rates, we simply divide the two numbers in the fraction. The resulting decimal form is the unit rate. Unit prices are a special type of unit rate comparing an item's cost per unit, such as dollars and cents.
      (2 votes)
  • blobby green style avatar for user Christian Montalvo
    Are all these examples right?
    (5 votes)
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  • duskpin seedling style avatar for user Abdulla aldhaheri
    900000000000000000000000000000000999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999900000000000000000000000000000000999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999900000000000000000000000000000000999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999900000000000000000000000000000000999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999900000000000000000000000000000000999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999v900000000000000000000000000000000999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999900000000000000000000000000000000999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999900000000000000000000000000000000999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999900000000000000000000000000000000999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999900000000000000000000000000000000999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999900000000000000000000000000000000999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999900000000000000000000000000000000999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999900000000000000000000000000000000999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999900000000000000000000000000000000999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999900000000000000000000000000000000999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999900000000000000000000000000000000999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999900000000000000000000000000000000999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999٩٩٩٩٩٩٩٩٩٩٩٩٩٩٩٩٩٩٩٩٩٩٩٩٩٩٩٩٩٩٩٩٩٩٩9000000000000000000000000000000009999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999000000000000000000000000000000009999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999000000000000000000000000000000009999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999000000000000000000000000000000009999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999000000000000000000000000000000009999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999
    (3 votes)
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  • blobby green style avatar for user 980031857
    we like men hope thi help
    (3 votes)
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Video transcript

- [Instructor] Let's do some example questions dealing with ratios. So we're told, "The table shows the number of people waiting "in line for different rides at an amusement park." So 15 people are waiting in line for the roller coaster, four people for the slingshot, 12 people waiting in line for the bumper cards, and 11 people in line for the round-up. "What is the ratio of people waiting in line "for the round-up "to the people waiting in line for the slingshot?" Pause this video and see if you can figure it out. So we wanna know the ratio of the people waiting in line for the round-up, this is the round-up right over here, to the number of people waiting in line for the slingshot. So, there's 11 people waiting in line for the round-up, and there are four people waiting in line for the slingshot, so the ratio is 11 to four. Or for every 11 people in line for the round-up, there are four people waiting in line for the slingshot. Let's do another example. "Katie loves to read! "In the last few months, she has read three graphic novels, "two mysteries, four science fiction novels, "and 21 comic books. "What is the ratio of sci-fi novels to comic books?" So once again, pause this video and try to work it out on your own. All right, so we wanted to know the ratio of sci-fi novels, so she has four sci-fi novels, the ratio of that to comic books. She has 21 comic books. So the ratio is for every four sci-fi novels, she has 21 comic books. Do you want me to do that in that other color? She has 21 comic books. So the ratio is four to 21, the ratio of sci-fi novels to comic books. Four sci-fi novels for every 21 comic books. Let's do one more example. This is strangely fun. "What is the ratio of apples to bananas?" Pause this video and try to figure it out. So let's see, there are one, two, three apples. So for every three apples, how many bananas are there? Well, there's one, two, three, four bananas. So the ratio of apples to, the ratio of apples to bananas is three apples for every four bananas. Order matters. If they said the ratio of bananas to apples, then this would be four to three, but they say apples to bananas, three to four. Three apples for every four bananas.