Converting gallons to quarts, pints, and cups
Converting gallons to quarts, pints, and cups
- How many cups are in 3 and 1/2 gallons?
- So before even addressing this question, let's just think
- about how large a cup is.
- Actually, I'll give you a little bit of overview of how
- many cups there are in a pint, how many pints in a quart, and
- how many quarts in a gallon.
- Let me just draw a cube here, and let's imagine
- that this is a gallon.
- The most common time we see a gallon is when you see a
- gallon of milk.
- So let's say that that whole thing is a gallon.
- You can imagine if it had a handle, it would be kind of a
- big gallon of milk.
- Now, there are 4 quarts per gallon.
- Let me write this over here.
- There are 4 quarts per gallon.
- So if I were to draw the quarts here, I could divide
- this gallon into 4 quarts, and then each of these sections
- would be a quart.
- So you would have 4 quarts.
- So this right here that I've just drawn in blue would be
- exactly 1 quart.
- And obviously, there's 4 of them in this entire gallon.
- Now, you can divide the quarts into pints.
- You have 2 pints per quart.
- So this quart that I drew here, I can divide it into 2,
- like that, and this little section that I'm highlighting
- in magenta is a pint.
- That is a pint right over there.
- And then finally, there are 2 cups per pint.
- So this pint right here, I can divide it into 2, and each of
- these will be a cup.
- So this section right here will be a cup.
- Now, we can go straight and figure out exactly how many
- cups there are per gallon.
- Actually, that might be an interesting way
- to think about it.
- If you have 4 quarts-- let's multiply it right here.
- So you have 4 quarts per gallon
- times 2 pints per quart.
- What does this give you?
- This gives you 4 times 2 is equal to 8.
- And then the quarts cancel out, and you
- have 8 pints per gallon.
- And that makes complete sense because we had 4 quarts in
- this gallon, and then each of those quarts
- have 2 pints in them.
- So 4 times 2.
- So 8 pints per gallon.
- And then we can multiply that times 2 cups per pint.
- So I could just copy and paste this right here.
- Actually, I should've cut and paste.
- Let me select it again.
- I want to do that so I get that real estate back.
- So edit, cut, edit, paste.
- There you go.
- So now you multiply this times 2 cups per pint.
- And the reason why this will work is because you have pints
- in the numerator.
- It cancels out with the pints in the denominator.
- And you will be left with-- I'll go back to the yellow-- 8
- times 2 is 16.
- In the numerator, we have cups per gallon.
- Now, we just figured how many cups there are per gallon.
- That makes sense.
- This section right here is exactly 1/16 of this entire
- cube, this entire gallon.
- But we haven't even answered our question.
- We want to figure out how many cups there are
- in 3 and 1/2 gallons.
- So let's write it over here.
- So we're concerned with 3 and 1/2 gallons.
- I don't like working with mixed numbers.
- I like to turn them into improper fractions.
- 3 and 1/2 is the same thing as 2 times 3 is 6, plus 1 is 7.
- This is the same thing as 7/2.
- If you divided 7 by 2, you would get 3 with a remainder
- of 1, or this would be 3 and 1/2, so this is
- the exact same thing.
- So we want to know how many cups are in 7/2 gallons.
- So what we want to do is end up with cups, and we want the
- gallons to cancel out.
- So we have gallons in the numerator right here.
- It's definitely not in the denominator.
- And so we want to divide by gallons.
- And then we're going to have a numerator.
- We have cups in the numerator.
- And how many cups are there per gallon?
- Well, we just figured that out.
- There are 16 cups per gallon.
- When you multiply these two quantities, the gallons will
- cancel out, and you'll just be left with cups, and that's
- what we wanted.
- So it's going to be 7/2 times 16.
- So this is going to be 7 times 16/2 cups.
- You could divide 16 by 2 to get 8.
- 2 divided by 2 is 1.
- So it just becomes 7 times 8 divided by 1, or just 7 times
- 8, which is 56.
- So this is equal to 56 cups.
- And this should make sense.
- This should be a much larger number because cups are a much
- smaller unit.
- So if you have 3 and 1/2 gallons, you will have many,
- many, many more cups in that 3 and 1/2 gallons,
- so this makes sense.
Be specific, and indicate a time in the video:
At 5:31, how is the moon large enough to block the sun? Isn't the sun way larger?
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You may or may not be familiar with the fact that the expression 7/2 x 16/1 can be written as 7x16/2x1. That's the same thing. So you can either write it as two separate fractions multiplied by each other, or you can let the numerators from both fractions stand in the numerator or on top of the bar and put a multiplication sign between them. You would do the same for the denominator.
Also he could have multiplied out the numerator and the denominator first, and then simplified it.
7/2 x 16/1 = 7x16/2x1 = 112/2
What's 112 divided by 2? It's 56! Or you could have simplified that first in the fraction, by dividing both the numerator and the denominator by the greatest common factor of both 112 and 2. So what's the greatest common factor of 112 and 2? It's 2! Number 2 is the only thing that goes into both 2 and 112.
But if you do the simplification at an early stage like Sal did where he simplified 16/2 to 8/1 and ultimately 8, you get a much smaller number at the end. Instead of dividing 112 by 2 the problem boils down to simple multiplication of 7 multiplied by 8.
You need to watch the fractions, multiples and factors videos to better understand this.
1 quart= 2 pints
1 gallon is the same as 8 pints
1 pint is 1/2 quarts
1pint=2cups or 16ounces
1quart=2pints,4cups, or 32 ounces
1gallon=4quarts, 8pints,16 cups,or 128 ounces
This tutorial could have been answered in a much shorter time if the method of conversion of ounces to gallons had been employed.
My approach was to do the calculations 1 cup = 8 oz & 1 gal = 128 oz 128/8=16 and then say 3.5 * 16. Of course the answer is 56.
then draw 4 Q in the g
then draw 2 P's in each q
and then then draw 2 c's in the p's
then it should look like a face
16 cups=1 gallon
1 cup = 8 fl oz
16 x 8= 128 fl oz
A tip anybody?
just as there are 4 quarts in a gallon.
Quart-5 letters, 4 in a gallon
Pint-4 letters, 2 in a quart
Cup-3 letters, 2 in a pint
I hope this helps you!
Many sources say pint comes from the French pinte, but no one knows where that comes from.
As for gallon it is from the Middle English gallon which is from Anglo-Norman French galon, which is from the base of medieval Latin galleta, galletum ‘pail, liquid measure,’ perhaps of Celtic origin.
I think it's fine question to ask because finding out the origins can help you understand and remember. For example lb, the abbreviation for pounds comes from Latin libra for scales. That can help you remember the strange abbreviation.
EDIT: This is wrong, the answer is 2 cups, I just looked at this and it didn't make much sense to me. There are 8 fluid ounces to a cup so you multiply both sides by 2 and you get 16(fluid ounces) = 2 cups
says what I need help on so plz answer as fast
8 pint / 1 galon * 2 cups / 1 pint
Why not multiply the pints with the pints? I mean I learned the process: if fraction 1 has pint at numerator,fraction 2 should have it at denominator,but I just don't understand why.
8 pints 2 cups
-------- * ------
1 gallon 1 pint
If you multiplied the pints, you would get
2 cupic gallons
Now does that make any sense? No!
When you multiply Sal's together, you will get
8 pint(s) * 2 cups
1 pint * 1 gallon
Notice that I switched around the gallon and the pint at the bottom to make the next step more understandable. This works perfectly due to the commutative property of multiplication.
Now remember how you can simplify
2 * 6
2 * 2
By getting rid of the 2 altogether? This works because they are being multiplied, which is the opposite of division. 12 / 4 is 3, just like 6 / 2
You can actually do that to get rid of the word "pint". Literally! You can cancel the units, by getting rid of the unit from the numerator and denominator from the number they are attached to. That might not be the best explanation, but it results in this:
8 * 2 cups
1 * 1 gallon
Now think about it, if you have 8 groups of 2 cups each (8 * 2 cups), you really have 16 cups! And if you have a group of a gallon each, you really have a gallon! So:
Which is actually the exact number of cups in a gallon! Cool huh?
The reason fraction 1 has it in the numerator and fraction 2 has it in the denominator, is that you can cancel out the word "pint".
Is it just because America hates mathematicians?
Around the world there are probably cultures who have names for that amount--if that is the amount a family wants to have of tapioca pudding and it is necessary to barter for it, then probably there is a name for it.
I haven't noticed anyone hating mathematicians--some people don't like math, though.
Like I said to someone else, if you are still wanting to see a video on that here is the link;
0.166 is close to 1/6
When you are actually using a recipe the amounts are not exact amounts because there is always some error in measuring.
We'll say for this example that there are 8 pints in a quart (might be wrong but it's the same method for solving) so well set up the problem 4 pints times 1 quart/8 pints. The pints cancel and so your left with 4/8 quarts. The 1 quart over 8 pints part is called the conversion ratio. So after its done you have 1/2 a quart. Most conversion ratios will be given, but some your expected to memorize.
Here is the link if you are still wondering.
i cant really explain that but it is used when saying things as in a minimum of food
like i ate 4quarts of lemonade yesterday
Metric makes it easy to convert from mL to L, or from mm to cm to m to km. It's also easy to convert from cubic cm to mL.
The imperial system has lots of units that are multiples of 2 or 3 of each other. That makes it easy to divide a recipe or cut a piece of lumber into halves, thirds, fourths, or sixths. Cutting a metric unit into thirds or sixths results in an irrational number.
I'd like to live in a world where we have the prefix-root naming convention of the metric system, but a base-12 numbering and measuring system. Then lots of these conversions and divisions would work out to nice whole numbers.
- A messsage from The imperials
If i saw a system that makes more sense than the metric one, I would jump right over to it and embrace it, sadly the Imperial system doesn't follow any pattern whatsoever.
Don't get me wrong, I'm not saying that you are silly in any way, i just don't understand why wouldn't you make your life easier for the future generations.
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When naming a variable, it is okay to use most letters, but some are reserved, like 'e', which represents the value 2.7831...
Thank the author
This is great, I finally understand quadratic functions!
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At 2:33, Sal said "single bonds" but meant "covalent bonds."
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