Rounding to the nearest hundred

Topic guide

What this worksheet practises

This worksheet provides practice on rounding numbers to the nearest hundred. This is a very common everyday estimation skill. It essentially asks: "Is this number closer to the hundred below it, or the hundred above it?".

Key method

You must locate the hundreds column and use the tens column to make your decision.

• Identify the digit in the hundreds column. This is your target digit. (Remember the order from the right: Units, Tens, Hundreds).
• Look at the digit immediately to its right, which will be the tens column. This is your "decider".
• If the decider is 5 or more (50 to 99), round the hundreds digit up to the next hundred.
• If the decider is 4 or less (0 to 49), keep the hundreds digit the same (rounding down).
• Replace both the tens and units digits with two placeholder zeroes.

Worked example

Round 8,462 to the nearest 100.

Step 1: Find the hundreds column. It is the 4.

Step 2: Look at the decider (the tens column). It is a 6.

Step 3: Because 6 is five or more, we round the 4 up to a 5.

Step 4: The number now begins 85. Replace the 62 with two zeroes.

The final answer is 8,500.

Common mistakes to avoid

The most common mistake is getting distracted by the units column. In the example 8,462, a student might look at the 2 at the end, decide "2 is less than 5", and incorrectly round down to 8,400. The units column is completely irrelevant. You only ever look at the single digit immediately next to your target (the tens column).

How to check your answer

Look at the last two digits of your final answer. If you are rounding to the nearest hundred, your answer must always end in exactly two zeroes (e.g. 300, 1500, 26700).