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Today we'll learn how to subtract multiples of 100 from 3-digit numbers using expanded form. This method helps us see exactly what happens to each place value. Let's start with an example: 456 minus 200. We'll break down both numbers into their place values to make the subtraction clearer. Now let's work through this step by step. First, we write 456 in expanded form as 400 plus 50 plus 6. Next, we write 200 in expanded form as 200 plus 0 plus 0. Then we subtract the hundreds: 400 minus 200 equals 200. The tens and ones stay the same since we're subtracting zero from them. Finally, we combine our results: 200 plus 50 plus 6 equals 256. Let's practice with another example: 738 minus 300. First, we write 738 in expanded form as 700 plus 30 plus 8. Then we write 300 as 300 plus 0 plus 0. We subtract the hundreds: 700 minus 300 equals 400. The tens and ones remain unchanged since we subtract zero from them. Finally, we combine: 400 plus 30 plus 8 equals 438. Now let's identify the key pattern. When we subtract multiples of 100 from 3-digit numbers, only the hundreds digit changes while the tens and ones digits stay exactly the same. For example, 567 minus 400 equals 167, where 67 remains unchanged. Similarly, 823 minus 500 equals 323, and 945 minus 600 equals 345. The general rule is: when subtracting d-hundred from a 3-digit number abc, the result is simply a-minus-d in the hundreds place, followed by the same bc in tens and ones. Welcome! Today we'll learn an easy way to subtract multiples of 100 from 3-digit numbers using expanded form. This method breaks down numbers into hundreds, tens, and ones, making subtraction much simpler. Let's start with an example: 456 minus 200. How can we solve this step by step? Let's break this down step by step. First, we write both numbers in expanded form. 456 becomes 400 plus 50 plus 6, and 200 becomes 200 plus 0 plus 0. Now we can see the place values clearly. In the hundreds place, we have 400 minus 200 equals 200. In the tens place, we have 50 minus 0 equals 50. In the ones place, we have 6 minus 0 equals 6. Finally, we combine the results: 200 plus 50 plus 6 equals 256. Let's try another example: 738 minus 500. First, we write both numbers in expanded form. 738 becomes 700 plus 30 plus 8, and 500 becomes 500 plus 0 plus 0. Next, we subtract by place value. In the hundreds place: 700 minus 500 equals 200. In the tens place: 30 minus 0 equals 30. In the ones place: 8 minus 0 equals 8. Finally, we combine the results: 200 plus 30 plus 8 equals 238. Notice how we only changed the hundreds digit! Let's look for patterns in our examples. In 456 minus 200 equals 256, notice that only the hundreds digit changed from 4 to 2. The tens and ones stayed the same. The same pattern appears in 738 minus 500 equals 238, where 7 becomes 2, but 3 and 8 remain unchanged. This gives us a quick rule: to subtract a multiple of 100, just subtract from the hundreds digit and keep the tens and ones the same! Let's summarize what we've learned. To subtract a multiple of 100 from a 3-digit number using expanded form: write both numbers in expanded form, subtract only the hundreds place, keep the tens and ones unchanged, then combine the results. For quick mental math, just subtract the hundreds digit and keep everything else the same. Try these examples: 684 minus 300 equals 384, 759 minus 500 equals 259, and 892 minus 700 equals 192. This method makes subtraction much easier and helps you understand place value better!