Placeholder Image

字幕列表 影片播放

  • - [Instructor] In this video

  • we're going to think about how fractions can be used

  • to represent things in the real world.

  • So here we're told that on the Sharks dive team

  • there are three divers in third grade.

  • There are eight total divers on the team.

  • What fraction of Sharks dive team is in third grade?

  • So pause this video and see if you can figure that out.

  • All right, so first of all they tell us

  • there are eight total divers on the team.

  • So maybe I'll represent each diver

  • with a little circle like this,

  • I'll try to make it look kind of like a diver,

  • so that's not quite a circle but you get the idea,

  • it looks like something kind of diving down.

  • So one, two, three, four, five, six, seven, and eight.

  • Now if we were to talk about just one diver here,

  • just like that, that would be one out of the eight.

  • Or we would often call that one eighth,

  • so eight with a h at the end.

  • That is one eighth right over there,

  • or I could represent it like this,

  • I could say this is an eighth, an eighth,

  • or I could say that this is equal to 1/8.

  • This is one of the eight members of our dive team.

  • Now they tell us that there are three divers in third grade,

  • what fraction of Sharks dive team is in third grade?

  • So that is, let's say it these three,

  • so there's three out of the eight.

  • So if you wanted to represent that as a fraction

  • you could represent it as 3/8 like this,

  • or you could represent it as,

  • if you wanted to write it out as a word,

  • three, instead of having it three over eight,

  • you could write three eighths like that.

  • If you were doing this on Khan Academy

  • there'd be some choices out there

  • where you'd pick one of the correct choice,

  • but you could represent the fraction of Sharks dive team

  • that is in third grade either as three over eight, 3/8,

  • or three and then spell out the word eighths.

  • Let's do another example.

  • Here we are told Yuma divided his clay

  • into four equal parts.

  • He made clay animals out of three of the parts.

  • What fraction of the clay did Yuma use to make clay animals?

  • So one again, pause this video, and think about it.

  • All right, so let's just imagine

  • that this is his clay, initially,

  • and he divides it into four equal parts.

  • And so let's say he divides it like this.

  • And let's say that I've divided it into four equal parts,

  • that these all have the exact amount of clay in it,

  • it's hand drawn so it's not going to be perfect

  • the way I drew it but let's assume they all have

  • the exact same amount of clay.

  • Now it says that he made clay animals

  • out of three of the parts.

  • So maybe, this part right over here,

  • he was able to make a clay animal out of,

  • this part right over here, he made a clay animal out of,

  • and then that part, right over there,

  • he made a clay animal out of.

  • So what fraction of the clay

  • did he use to make clay animals?

  • So what would you call each of the equal parts?

  • So if I were to just focus on that right over there,

  • you would call that a fourth, a fourth.

  • You could also represent it as one fourth, like that,

  • or you could represent it as 1/4.

  • That's if you were to just circle one of these equal parts,

  • that one, or that one, or that one, or that one.

  • Now if you're talking about all of his clay,

  • what are you talking about?

  • Well you could view it as four fourths, four fourths,

  • or four over four, this would also be read four fourths.

  • That would be referring to

  • all one, two, three, four of his clay.

  • Now if you wanted to say what fraction of the clay

  • did Yuma use to make clay animals,

  • we can see that three of the fourths,

  • were used to make clay animals.

  • So to answer that question,

  • we would say three of the fourths,

  • so three fourths were used to make clay animals.

  • You can also express that as a fraction.

  • You could also write that as 3/4 like this.

  • You would read these the same,

  • three fourths, or three fourths.

  • Three out of the four equal sections of clay

  • were used to make the clay animals.

- [Instructor] In this video

字幕與單字

單字即點即查 點擊單字可以查詢單字解釋

B1 中級

小數的背景 (Fractions in context)

  • 10 0
    林宜悉 發佈於 2021 年 01 月 14 日
影片單字