Regrouping Multiple Place Values

Question

Subtract: 500 - 258

Exact difference:
* I can't borrow from the tens place, because there are 0 tens.
* I will borrow from the hundreds place to make ____ tens
* I'm giving one of those tens to the ones place.
Estimated difference:
500
- 258
______

500
- 250
______

Answer 1

Let's break down the subtraction step by step, including both the exact calculation and the estimated calculation.

Exact Difference of 500 - 258

1. We start with the numbers:

   • 500 (5 in the hundreds, 0 in the tens, 0 in the ones)
   • 258 (2 in the hundreds, 5 in the tens, 8 in the ones)

2. We need to subtract:

   • From the ones place: 0 - 8.
     • Since we can't subtract 8 from 0, we need to borrow.

3. Borrows:

   • We can't borrow from the tens place since there are 0 tens. Therefore, we have to go to the hundreds place.
   • We will borrow from the hundreds place (5) to make 10 tens. This leaves us with 4 hundreds.
   • With the 10 tens we just created, we can give one of those tens to the ones place making it 10 ones in the ones place.

4. Now, the numbers look like this:

   • Hundreds: 4
   • Tens: 9 (because we borrowed 1 ten from the tens place)
   • Ones: 10

5. We can now subtract:

   • Ones place: 10 - 8 = 2 (write 2 in the ones place).
   • Tens place: 9 - 5 = 4 (write 4 in the tens place).
   • Hundreds place: 4 - 2 = 2 (write 2 in the hundreds place).

So, the exact difference:

Exact difference: 500 - 258 = 242

Estimated Difference

1. For estimation, we can round 258 to the nearest ten. In this case, 258 is closer to 250.

2. Now we subtract the rounded number from 500:

   • 500
   • • 250

   ---

   • 250

So the estimated difference:

Estimated difference: 500 - 250 = 250

Summary

• Exact difference: 242
• Estimated difference: 250