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MAP Recommended Practice
Course: MAP Recommended Practice > Unit 34
Lesson 32: Dividing fractions and whole numbers word problemsDividing whole numbers by fractions: word problem
Learn to solve a word problem that involves dividing a whole number by a unit fraction. Created by Sal Khan.
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- Can't you just multiply 4 and 5 in the beginning?(111 votes)
- Yes you could have, but you will be more sure of your answer if you do it Sal's way (even though he is basically doing that, but step by step).(85 votes)
- what is a potpurri?(65 votes)
- a mixture of dried petals and spices placed in a bowl to perfume a room.(11 votes)
- What is potpourri(14 votes)
- It seems to be there is two definitions of potpourri. The definition I know is "a little bit of everything" or "everything". Using context clues, I think potpourri is kind of like a trail mix of some kind of food. By trail mix, I mean, "a whole bunch of different types of foods". What kind of food, I don't know, but I hope I helped!(0 votes)
- Sal how do I make a fraction out of 5 and divide it by 1 half ( not a home work question) :)(5 votes)
- 5/1 and 5 divide by 1/2 equals 2 1/2 (i think)(1 vote)
- what is potpourri?(4 votes)
- A mixture of dried petals and spices placed in a bowl or small sack to perfume clothing or a room(3 votes)
- i need help please answer soon please(4 votes)
- Let’s say I had to do 4 divided by 1/2. 1/2 goes into 1 2 times, so I have to divide 4 by 2. So the answer is 2. Now for something a little harder. 12 divided by 1/6. Since 1/6 goes into 1 6 times, you do 12 divided by 6, which is 2. This is just the basics. Ask if you want a little more information.(3 votes)
- Ok, I'm confused, If I had 3 cups of something and only wanted a third of it would that equation not be 3 divided by 1/3. If so the answer is nine instead of one?(3 votes)
- Here is how I look at it. Words mean things. When you say "a third of it," the word "of" is the key: "of" means to multiply. So, "a third of it" which is "a third of 3 cups". Do a simple substitution of "times" for "of": "a third times 3 cups".
So 1/3 x 3 cups = 1 cup(5 votes)
- could you just say 4 times 5(3 votes)
- Yes, you could.. but some schools want you to show your work.(3 votes)
- do you get a different answer when you do 5/6divided by 2 or 2 dividded by 5/6(3 votes)
- Yes you do get different answers! The order in which you divide numbers makes a difference.
5/6 divided by 2 = 5/6 times 1/2 = 5/12.
2 divided by 5/6 = 2 times 6/5 = 2/1 times 6/5 = 12/5.
5/12 is not the same as 12/5. 5/12 is less than 1, but 12/5 is greater than 1.
Have a blessed, wonderful day!(3 votes)
- so its just the number divided by the denominator(4 votes)
Video transcript
Tracy is putting out
decorative bowls of potpourri in each room of the
hotel where she works. She wants to fill each bowl
with 1/5 of a can of potpourri. If Tracy has 4 cans of
potpourri, in how many rooms can she place a
bowl of potpourri? So she has 4 cans, and
she wants to divide this 4 cans into groups
of 1/5 of a can. So if you have 4 of
something and you're trying to divide it into
groups of a certain amount, you would divide by
that amount per group. So you want to divide 4 by 1/5. You want to divide 4 cans of
potpourri into groups of 1/5. So let's visualize this. Let me draw one can of
potpourri right over here. So one can of potpourri can
clearly be cut up into 5/5. We have it right over here. 1, 2, 3, 4, 5. So 1 can of potpourri
can fill 5 bowls if you put 1/5 in each bowl. Now, we have 4 cans. So let me paste these. So 2, 3, and 4. So how many total bowls of
potpourri can Tracy fill? Well, she's got 4 cans. So this is going to
be equal to-- let me do this is the right
color-- this is going to be equal to, once
again, she has 4 cans. And then for each
of those cans, she can fill 5 bowls of potpourri
because each bowl only requires a 1/5 of those cans. So this is going to be the
same thing as 4 times 5. Or we can even write
this as 4 times 5 over 1. 5 is the same
thing as 5/1, which is the same thing
as 4 times 5, which, of course, is equal to 20. She can fill 20 cans-- or I
should say, with her 4 cans, she can fill 20
bowls of potpourri. Now, just as a
review here, we've already seen that
dividing by a number is equal to multiplying
by its reciprocal. And we see that right over here. Dividing by 1/5
is the same thing as multiplying by the
reciprocal of 1/5, which is 5/1. So she could fill up
20 bowls of potpourri.