Video Transcript
Fill in the blanks. 27 pounds seven ounces equals what ounces.
There is some abbreviations in this problem. Let’s remind ourselves what they stand for. We can see two units of measurement, and they’re both ways of measuring how heavy something is. Lb is the abbreviation we use to represent pounds. When we say pounds, we’re talking about pounds of weight, not pounds in money. And then, oz is the abbreviation that we use to represent ounces. And, of course, these are another way to measure how heavy something is, except these are a smaller unit of measurement than a pound.
In our problem, we’re given one measurement, which is 27 pounds seven ounces. And we’re told that it is equal to a number of ounces. We already have seven ounces, so perhaps we could write the seven already. But how many ounces are there in 27 pounds? If we could calculate this value, we could add it to seven ounces to find the answer. To help us convert 27 pounds into ounces, we’re going to need one fact. And that’s the number of ounces in one pound. One pound is the same as 16 ounces. So, to convert 27 pounds into ounces, we need to multiply 27 by 16.
To make it easier to multiply these two numbers, we could partition the number 16. We could split up 16 into 10 and six. So, if we multiply 27 by 10 and then 27 by six and then add the two results together, we could find the answer to 27 multiplied by 16. We know that when we multiply a number by 10, the digits shift one place to the left. So, 27 multiplied by 10 is going to be 270. To help us find the answer to 27 multiplied by six, we can use what we’ve just found out to help us. Five lots of 27 is going to be half of the number we’ve just found. Half of 200 is 100, and half of 70 is 35. So, we know 27 multiplied by five is going to be 135.
So, to find six lots of 27, we need to add one more lot of 27. And if we add each digit, we find that the answer is 162. Now that we’ve multiplied our two parts, we need to add them back together to find the answer to 27 multiplied by 16. Zero ones plus two ones equals two ones. Seven plus six equals 13. So, seven tens plus six tens equals 13 tens. It’s just the same as 130. And then finally, two hundreds plus one hundred plus the one hundred we’ve exchanged equals four hundreds.
So, now we can complete the value of 27 pounds. So, now we can complete the value of 27 pounds. We know that 27 pounds is worth 432 ounces. But remember, we don’t just need to convert 27 pounds into ounces, we also have an extra seven ounces on the end. And if we add these seven ounces onto 432, we get a total of 439. So, we can complete the blank with this missing number. 27 pounds seven ounces is equal to 439 ounces. Our missing number is 439.