what if the two top numbers are bigger than the bottom number like this: 2/8+7/8=9/8

I think you need to multiply the two denominators that aren't the same and find the LCM

Where do you get the spider problem when its not in in the practice?

It's just an example. Not all video problems are the same as practice problems.

So, fractions do not only represent equal parts of a whole, but are groups or things?

True. If a class has 30 students and 28 are present at morning assembly then 28/30 are present. The whole in this case is all the students of the class combined. (This can be simplified to 14/15 though in a real case scenario it probably wouldn't be). You can make such a set out of whatever you feel like: books you've read out of all the books you own. Capitals you've visited out of all the capitals in the world etc.

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Course: Staging content lifeboat > Unit 14

Lesson 15: Adding and subtracting fractions: word problems

Fraction word problem: spider eyes

Name: Fraction word problem: spider eyes
Uploaded: 2013-08-08T20:31:07Z
Description: Sal solves a fraction word problem about spider eyes. The fractions have common denominators.

CCSS.Math:

4.NF.B.3

4.NF.B.3d

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Sal solves a fraction word problem about spider eyes. The fractions have common denominators. Created by Sal Khan.

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cameronjdoud
Posted 8 years ago. Direct link to cameronjdoud's post “what if the two top numbe...”
what if the two top numbers are bigger than the bottom number like this: 2/8+7/8=9/8
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- makai.selig
  Posted 7 years ago. Direct link to makai.selig's post “I think you need to multi...”
  I think you need to multiply the two denominators that aren't the same and find the LCM
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Carmen Gomez
Posted 7 years ago. Direct link to Carmen Gomez's post “Where do you get the spid...”
Where do you get the spider problem when its not in in the practice?
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- Giana
  Posted 7 years ago. Direct link to Giana's post “It's just an example. No...”
  It's just an example. Not all video problems are the same as practice problems.
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CruzIsabella2029
Posted 6 years ago. Direct link to CruzIsabella2029's post “what are spider eyes in m...”
what are spider eyes in math
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(9 votes)
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- ikigai54321
  Posted 5 months ago. Direct link to ikigai54321's post “its just a demonstration.”
  its just a demonstration.
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  (1 vote)
Jorge Daniel Garcia
Posted 8 years ago. Direct link to Jorge Daniel Garcia's post “So, fractions do not only...”
So, fractions do not only represent equal parts of a whole, but are groups or things?
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(5 votes)
Answer
- Axel Aldrich
  Posted 7 years ago. Direct link to Axel Aldrich's post “True. If a class has 30 s...”
  True. If a class has 30 students and 28 are present at morning assembly then 28/30 are present. The whole in this case is all the students of the class combined. (This can be simplified to 14/15 though in a real case scenario it probably wouldn't be).
  
  You can make such a set out of whatever you feel like: books you've read out of all the books you own. Capitals you've visited out of all the capitals in the world etc.
  Button navigates to signup page
  (8 votes)
katter21
Posted 6 years ago. Direct link to katter21's post “it makes sents and its ma...”
it makes sents
and its making me sherver
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Himanshu Rana
Posted 5 years ago. Direct link to Himanshu Rana's post “does this mean that spide...”
does this mean that spider can see with 360degree??
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(7 votes)
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- 🌮🥑maxi boi17🎮☣
  Posted 4 months ago. Direct link to 🌮🥑maxi boi17🎮☣'s post “yes thay can”
  yes thay can
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ohmyninja
Posted 7 years ago. Direct link to ohmyninja's post “Is it just me or does the...”
Is it just me or does the first spider have 6 eyes?
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- Kris Dryden
  Posted 3 months ago. Direct link to Kris Dryden's post “the other two are hidden”
  the other two are hidden
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  (2 votes)
JoshuaC
Posted a month ago. Direct link to JoshuaC's post “The pictures made me unco...”
The pictures made me uncomfortable
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Cybil899
Posted 3 years ago. Direct link to Cybil899's post “why is this even a chat h...”
why is this even a chat here and we feel like adults? XD
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- 31gcooga
  Posted a month ago. Direct link to 31gcooga's post “l o l”
  l o l
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Al HarathF
Posted 3 years ago. Direct link to Al HarathF's post “this is creepy i am scara...”
this is creepy i am scarad from spiders
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Video transcript

A common house spider has 8 eyes. If a spider is looking at you with its 2 front eyes and 3 of its other eyes, what fraction of its eyes are looking at you? And just to show that we're not making this stuff up, this is actually pictures of spiders. And you see in every one of these pictures they have eight eyes, even this one's got other eyes right over here-- 1, 2, 3, 4, 5, 6, 7, 8. I never even realized this. This is actually quite creepy. But anyway, let's actually focus on the problem. So it's looking at you with 2 of its 8 eyes. So the 2 front eyes represent what fraction of the eyes? Well, it represents 2 of the 8 eyes. You could look at it right over here. You have 8 eyes. We have the 2 front eyes. That's 1 and 2 of the 8. And it says it's also looking at us with 3 of its other eyes. So it's also looking at us with 3 of the 8 eyes. And so you can imagine that might be that one, that one, and that one. So this is really about adding fractions. This is about adding 2/8 of something to 3/8 of something. So what fraction of its eyes are looking at us? Well, it's still going to be a fraction of 8. It's going to be still out of 8-- 2 plus 3 over 8, which is just going to be equal to 5/8 of the eyes. 5 out of the 8 eyes are looking at us. And we see it right over here-- 1, 2, 3, 4, 5. 5 of the total of 8 eyes are looking at us in a fairly creepy way.