Rounding to Nearest 10 and 100 Worksheets in Grade 4

Complete worksheets on rounding to nearest 10 and 100: place value, rounding rules, step-by-step methods, and practice exercises.

Worksheet Summary & Key Concepts
S Comprehensive Summary
Key Definitions:

Rounding: Making a number simpler but keeping its value close to what it was

Place Value: The value of a digit based on its position in a number (ones, tens, hundreds, etc.)

Nearest 10: The closest multiple of 10 to a given number

Nearest 100: The closest multiple of 100 to a given number

Estimation: Using rounded numbers to get an approximate answer

Rounding to Nearest 10 Method:
  1. Identify place values: Locate tens and ones digits
  2. Look at ones digit: Only the ones digit determines rounding direction
  3. Apply rule: If ones digit ≥ 5, round UP; if ≤ 4, round DOWN
  4. Change trailing digits: Set all digits to the right of tens to zero
Rounding to Nearest 100 Method:
  1. Identify place values: Locate hundreds, tens, and ones digits
  2. Look at tens digit: Only the tens digit determines rounding direction
  3. Apply rule: If tens digit ≥ 5, round UP; if ≤ 4, round DOWN
  4. Change trailing digits: Set all digits to the right of hundreds to zero
Rounding to 10
Look at ONES digit
Rounding to 100
Look at TENS digit
Rule
5 and above → ROUND UP
Core Rules:

• Ones digit rule (to nearest 10): If ones digit ≥ 5, round up; if ≤ 4, round down

• Tens digit rule (to nearest 100): If tens digit ≥ 5, round up; if ≤ 4, round down

• Halfway cases: When exactly halfway (digit = 5), round up

• Trailing zeros: Digits to the right of the rounding place become zeros

Memory trick: "5 and above, let it fly" - round up when target digit ≥ 5!
Focus rule: For nearest 10, focus on ones; for nearest 100, focus on tens.
Halfway rule: When exactly halfway (digit = 5), always round up.
Verification: Check that your answer is a multiple of 10 or 100.
Rounding Examples & Practice
Rounding Rules
To Nearest 10 and 100
Rounding to Nearest 10
Example 1: Round 67 to nearest 10

• Ones digit is 7 (≥ 5) → Round UP to 70

Example 2: Round 42 to nearest 10

• Ones digit is 2 (≤ 4) → Round DOWN to 40

Example 3: Round 35 to nearest 10

• Ones digit is 5 (= 5) → Round UP to 40

Example 4: Round 156 to nearest 10

• Ones digit is 6 (≥ 5) → Round UP to 160

Rounding to Nearest 100
Example 1: Round 567 to nearest 100

• Tens digit is 6 (≥ 5) → Round UP to 600

Example 2: Round 423 to nearest 100

• Tens digit is 2 (≤ 4) → Round DOWN to 400

Example 3: Round 750 to nearest 100

• Tens digit is 5 (= 5) → Round UP to 800

Example 4: Round 1,248 to nearest 100

• Tens digit is 4 (≤ 4) → Round DOWN to 1,200

Common errors: Looking at wrong digit, forgetting to change trailing digits to zero, misapplying halfway rule.
Key memorization: Focus on the digit one place to the right of the rounding place.
Practice Worksheet Problems
W Worksheet Problems
Part A: Round to Nearest 10
Number Ones Digit Direction Answer
24 4 Down 20
78 8 Up 80
155 5 Up 160
432 2 Down 430
679 9 Up 680
Part B: Round to Nearest 100
Number Tens Digit Direction Answer
347 4 Down 300
689 8 Up 700
1,250 5 Up 1,300
4,523 2 Down 4,500
7,845 4 Down 7,800
Total Problems
10
Completed
0
Remaining
10
Worksheet Tips:

• Always identify place values first

• Focus on the correct digit

• Remember the "5 and above" rule

• Set trailing digits to zero after rounding

• Check your answer is a multiple of 10 or 100

Detailed Rounding Guide
Rounding Process
Step-by-Step Guide
Understanding Place Values:

Ones place: Rightmost digit

Tens place: Second from right

Hundreds place: Third from right

Thousands place: Fourth from right

Complete Rounding Process:
  1. Identify the rounding place: Determine if rounding to nearest 10 or 100
  2. Locate the target digit: Find the digit one place to the right of the rounding place
  3. Apply the rule: If target digit ≥ 5, round up; if ≤ 4, round down
  4. Change digits: Keep digits to the left of rounding place, set others to zero
  5. Verify: Check that your answer makes sense
Visual aid: Use number lines to see where numbers fall between multiples.
Practice pattern: Start with simple numbers, then progress to larger ones.
Check reasonableness: Your rounded number should be close to the original.
Use in context: Apply rounding to real-world problems like estimation.
Applications: Estimating costs, population figures, distances, and inventory counts.
Real-world contexts: Shopping, measuring, counting, and making quick calculations.
Essential formulas and rules:

• Nearest 10 Rule: Look at ones digit, round up if ≥ 5, down if ≤ 4

• Nearest 100 Rule: Look at tens digit, round up if ≥ 5, down if ≤ 4

• Halfway Convention: When target digit = 5, round up

• Trailing Zeros: After rounding, digits to the right become zeros

• Estimation Strategy: Rounding simplifies numbers for easier calculation

Questions & Answers

Question: I'm confused about when to round to the nearest 10 versus the nearest 100. How do I know which one to do?

Answer: The problem will usually tell you which one to do! Look for specific instructions:

  • "Round to the nearest 10": Look for the tens place and focus on the ones digit
  • "Round to the nearest 100": Look for the hundreds place and focus on the tens digit

Examples:

  • Round 247 to the nearest 10 → Focus on ones digit (7) → Answer: 250
  • Round 247 to the nearest 100 → Focus on tens digit (4) → Answer: 200

The key is to identify which place value you're rounding to, then look at the digit immediately to its right.

Question: When I round 350 to the nearest 100, it seems like it should stay the same since it ends in 50. Why does it become 400?

Answer: This is a common source of confusion! When rounding to the nearest 100, you only look at the tens digit, not the entire last two digits.

In 350:

  • The hundreds digit is 3
  • The tens digit is 5
  • The ones digit is 0

Since the tens digit is 5 (which equals 5), we round UP to the next hundred: 400.

Remember the rule: when the target digit (tens digit for nearest 100) is 5 or greater, we round up. The ones digit doesn't matter when rounding to the nearest 100.

Question: I sometimes forget to change the digits to the right of the rounding place to zero. Any tips?

Answer: This is a very common mistake! Here are some strategies to help:

  • Circle the rounding place: Circle the digit you're rounding to, then cross out everything to the right
  • Replace with zeros: After crossing out, write zeros in those positions
  • Check your work: Make sure your answer is a multiple of 10 (for nearest 10) or 100 (for nearest 100)

Example: Rounding 473 to nearest 10:

  • Focus on tens place (7), ones digit is 3 (≤ 4) → Round down
  • Cross out the 3, replace with 0 → 470
  • Check: 470 is a multiple of 10 ✓

Practice this process several times until it becomes automatic!