Estimate Numbers to 1000 – Printable Math Worksheet for 8‑Year‑Olds (Grade 3) | Rounding & Place Value Practice

Instructions

Estimating is like making a smart guess! We can round numbers to make them simpler and easier to work with, especially when we don't need an exact answer. Let's practice rounding to the nearest ten and hundred.

Part 1: Rounding Rollercoaster - To the Nearest Ten!

To round to the nearest ten, look at the digit in the ones place.

• If the ones digit is 5, 6, 7, 8, or 9, you round up to the next ten. (Example: 48 rounds up to 50)
• If the ones digit is 0, 1, 2, 3, or 4, you round down to the ten you just passed. (Example: 42 rounds down to 40)

Round each number below to the nearest ten.

1. 87 → ____________
2. 32 → ____________
3. 155 → ____________
4. 291 → ____________
5. 98 → ____________
6. 463 → ____________

Part 2: High-Flying Hundreds - To the Nearest Hundred!

To round to the nearest hundred, look at the digit in the tens place.

• If the tens digit is 5, 6, 7, 8, or 9, you round up to the next hundred. (Example: 271 rounds up to 300)
• If the tens digit is 0, 1, 2, 3, or 4, you round down to the hundred you just passed. (Example: 635 rounds down to 600)

Round each number below to the nearest hundred.

1. 481 → ____________
2. 729 → ____________
3. 150 → ____________
4. 899 → ____________
5. 345 → ____________
6. 962 → ____________

Part 3: Estimation Detective!

Read the stories and use your rounding skills to find an estimated answer. Show your rounded numbers!

1. A candy store has a big jar with 312 gumballs and a small jar with 89 gumballs. About how many gumballs are there in total?

First, round each number to the nearest ten.

312 → _______

89 → _______

Now add your rounded numbers: _______ + _______ = _______

There are about ___________ gumballs.

2. Maya read a book with 478 pages. Liam read a book with 221 pages. About how many more pages did Maya read than Liam?

First, round each number to the nearest hundred.

478 → _______

221 → _______

Now subtract your rounded numbers: _______ - _______ = _______

Maya read about ___________ more pages.

Part 4: Number Line Challenge

Place an X on the number line to show approximately where each number belongs.

1. Show where 280 is:

200 <--------------------------------------------------> 300

2. Show where 615 is:

600 <--------------------------------------------------> 700

3. Show where 450 is:

400 <--------------------------------------------------> 500

Answer Key

Part 1: Rounding Rollercoaster - To the Nearest Ten!

1. 87 → 90
2. 32 → 30
3. 155 → 160
4. 291 → 290
5. 98 → 100
6. 463 → 460

Part 2: High-Flying Hundreds - To the Nearest Hundred!

1. 481 → 500
2. 729 → 700
3. 150 → 200
4. 899 → 900
5. 345 → 300
6. 962 → 1000

Part 3: Estimation Detective!

1. Gumballs problem:

312 → 310

89 → 90

310 + 90 = 400

There are about 400 gumballs.

2. Books problem:

478 → 500

221 → 200

500 - 200 = 300

Maya read about 300 more pages.

Part 4: Number Line Challenge

1. Show where 280 is: (The X should be far to the right, close to 300)

200 <-----------------------------------------X---------> 300

2. Show where 615 is: (The X should be very close to the left, near 600)

600 <---X-----------------------------------------------> 700

3. Show where 450 is: (The X should be exactly in the middle)

400 <-------------------------X-------------------------> 500