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4th grade
Course: 4th grade > Unit 7
Lesson 3: Comparing fractions with unlike denominators visuallyComparing fractions: tape diagram
Sal compares fractions with unlike denominators by drawing bars.
Want to join the conversation?
- Can you also compare fractions by rewriting them as decimals?(71 votes)
- Yes - sometimes that is an easier.
For example if you have 7/10 and 3/4 and you know that 7/10 = 0.7 and 3/4 = 0.75, so 3/4 is bigger.
Sometimes it is harder. For example: you wouldn't want to change 3/7 to a decimal, if you didn't have to.(53 votes)
- i agree can you also compare fractions by rewriting them as decimals(13 votes)
- Yes, converting to decimals is one method of comparing fractions. This method is easiest when the denominators are “nice” (for example, 2, 4, 5, 8, 10, 20, etc).
Have a blessed, wonderful day!(8 votes)
- Is this going to get harder or easier because I’m in forth and they haven’t taught this yet but right now this is easy but will it get harder or easier?(11 votes)
- im doing a challenge DO NOT UPVOTE ME or i lose(7 votes)
- Am i the only one here that thinks he explains the homework in a more complicated way then what is needed?
He is explaining in a confusing way(5 votes)- you have ADHD then because those who dont will understand(3 votes)
- when do u use fractions?(2 votes)
- When u r using a protractor(2 votes)
- i love math so much .(5 votes)
- i do not know how to do this(4 votes)
- what do u mean(3 votes)
- What is a tape diagram ?(4 votes)
- A tape diagram is a diagram like the one he is drawing in the video(2 votes)
Video transcript
- [Voiceover] What I
wanna do in this video is compare the fractions 3/4 and 4/5, and I wanna do this visually. So what I'm gonna do is
I'm gonna have two copies of the same whole, so
let me just draw that, but I'm gonna divide the first one, so this is one whole right
over here, this rectangle, when we draw the whole thing. So this is a whole, and right below that,
we have the same whole. We have a rectangle of
exactly the same size. Now you might notice
that I've divided them into a different number of equal sections. In the top one, I've divided
it into four equal sections because I am concerned with fourths so I've divided this
top whole into fourths and I've divided this bottom
whole, or this bottom bar or this bottom rectangle, into fifths, or five equal sections. So let's think about what 3/4 represent. So that's gonna be one of
the fourths, right over here, two of the fourths, and then three of the fourths. And what is 4/5 going to be? Well, 4/5 is going to be one fifth, two fifths, three fifths, and four fifths. So when you look at
them visually, remember, we're taking fractions of the same whole. This is 3/4 of that rectangle, this is 4/5 of a same-sized rectangle. It wouldn't make any
sense if you're doing it for different shapes or
different sized rectangles. We just divided them
into different sections and you see that if you
have four of the fifths, that that is going to be more than three of the fourths, and so 4/5 is greater than 3/4 or you could say 3/4 is less than 4/5, or any way you wanna think about it. The symbol you wanna use always
opens to the larger number. 4/5 is larger than 3/4, so the large end of our
symbol is facing the 4/5, so we would say 3/4 is less than 4/5.