About this video
Mary splits 15,000 milliliters of tea equally into 8 pitchers, so each holds 15,000 / 8 = 1,875 mL. Guests drink 6 pitchers, leaving 2 pitchers, or 2 x 1,875 = 3,750 mL. Using 1,000 mL = 1 L, the leftover tea is 3 liters and 750 milliliters.
You'll be able to
- use division to share a quantity equally.
- solve a multi-step word problem about liquid volume.
- write milliliters as a whole number of liters and milliliters.
Key words
- milliliter (mL)
- A small metric unit of volume; 1,000 milliliters make 1 liter.
- liter (L)
- A metric unit of volume equal to 1,000 milliliters.
- divided equally
- Shared so that every group gets exactly the same amount.
- leftover
- The amount that remains after some has been used.
Transcript
Mary made 15,000 milliliters of tea for a party, and she served the tea divided equally in 8 pitchers. Her guests drank 6 pitchers of tea. How much tea did Mary have leftover? Write the answer as a whole number of liters and a whole number of milliliters. So let's think about this a little bit.
She's got 8 pitchers. So let's visualize these pitchers. So let me see if I can, so let me draw a pitcher here. So this is one pitcher. I'll do my best to draw a nice pitcher. So this is one pitcher. And she's going to put the same amount of tea in every pitcher.
So the same amount of tea in every pitcher. Let me copy and paste this, so copy and paste. So she's going to have 8 of these. So that's 2, 3, 4, 5, 6, 7, and 8. So she wants to put the exact same amount of fluid in each of these 8. So she's going to divide evenly the 15,000 milliliters into 8 pitchers.
So that's straight up division. She's going to start with 15,000 milliliters, And she's going to divide it by 8. She's going to divide into 8 equal groupings or 8 equal pitchers with the same amount in each of the pitchers. So 8 goes into, it doesn't go into 1, it goes into 15 one time.
1 times 8 is 8, subtract 15 minus 8 is 7. So bring down a 0. 8 goes into 70, 8 times. 8 times 8 is 64. Subtract, we get a 6, bring down another zero. 8 goes into 60 seven times. 7 times 8 is 56. Subtract again, we get a 4 and then bring down a zero again. 8 goes into 40 exactly 5 times.
5 times 8 is 40. And we're not left with a remainder. So if we divide 15,000 milliliters into 8 equal sections, each pitcher is going to have exactly 1,875 milliliters. So that's 1,875 milliliters. But that's not what they're asking us for. They tell us that her guests drank 6 pitchers of tea, and how much tea did Mary have leftover.
So the guests drank 1, 2, 3, 4, 5, 6, leaving 2 pitchers left. How much total tea is going to be in that? It's going to be 2 times 1,875, or 1,875 milliliters times 2. Figure out what that is. 2 times 5 is 10, 2 times 7 is 14 plus 1 is 15. 2 times 8 is 16 plus 1 is 17.
2 times 1 is 2 plus 1 is 3. So what she's left with, what she's leftover with is 3,750 milliliters. Now they want our answer in terms of a whole number of liters and a whole number of milliliters. And we just have to remind ourselves that 1,000 milliliters is equal to 1 liter.
So you could rewrite this. This is the total number of milliliters that she's left with. We could rewrite this as 3,000 milliliters plus 750 milliliters. Now the reason I wrote it this way is because if 3,000 milliliters-- this is literally 3,000 one-thousandths of a milliliter.
We already saw that 1,000 milliliters is equal to 1 liter, so this piece right over here, this is equal to 3 liters. This is equal to 3 liters. So if we wanted to write it as a whole number of liters and a whole number of milliliters, this would be 3 liters and 750 milliliters.
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