GCSE Maths Practice: place-value-and-rounding
This foundation-level question tests rounding to the nearest hundred. You’ll use the tens digit to decide whether to round up or keep the hundreds digit the same. This skill is used in estimation and large-number calculations across science, finance, and everyday life.
Exam tip: When rounding to the nearest hundred, underline the hundreds digit and circle the tens digit. If the tens digit is 5 or more, round up; if it’s 4 or less, round down. 985.67 is closer to 1000 than 900, so the correct answer is 1000.
Try more: 132, 860, 1499.
Concept Overview
Rounding to the nearest hundred is a simple but powerful skill that helps make numbers easier to work with. In real life, we often use rounding when we don’t need an exact figure — for example, when estimating money, distances, or population sizes. The hundreds place is two digits to the left of the decimal point. When rounding to this place, we look at the tens digit to decide what happens.
If the tens digit is 5 or greater, we increase the hundreds digit by 1. If it is 4 or less, we keep the hundreds digit the same. Then we replace all smaller digits (tens, ones, and decimals) with zeros to show that the number has been rounded to the nearest hundred.
Step-by-Step Method
- Identify the hundreds digit: In 985.67, the hundreds digit is 9.
- Check the tens digit: The tens digit is 8.
- Apply the rounding rule: 8 ≥ 5 → round up → 9 becomes 10.
- Replace all digits after the hundreds place with zeros: 985.67 → 1000.
Worked Examples
Example 1. Round 642 to the nearest hundred.
- Hundreds = 6; tens = 4.
- 4 < 5 → keep 6 the same → 600.
Example 2. Round 1789 to the nearest hundred.
- Hundreds = 7; tens = 8.
- 8 ≥ 5 → increase hundreds to 8 → 1800.
Example 3. Round 2499 to the nearest hundred.
- Hundreds = 4; tens = 9.
- 9 ≥ 5 → round up → 2500.
Common Mistakes
- Checking the wrong digit: Some learners look at the ones digit instead of the tens digit.
- Rounding to the wrong place value: Rounding 985.67 to 990 means rounding to the nearest ten, not hundred.
- Forgetting to zero out digits: Always replace all digits to the right of the hundreds place with zeros — it shows that precision stops there.
- Dropping zeros unnecessarily: 1000 must include all zeros — writing just “1” changes the value completely.
Real-Life Applications
Rounding to the nearest hundred appears in many everyday and professional contexts:
- Money: A product priced at £985.67 might be described as “around £1000”. This makes estimates easier when planning a budget.
- Population: A town with 985 people can be rounded to 1000 when writing general statistics.
- Distance: A car journey of 985.67 metres can be rounded to 1000 metres (1 km).
- Data presentation: In reports or charts, rounding large numbers improves clarity and helps avoid misleading precision.
Using rounding appropriately saves time and makes figures simpler to communicate without losing overall accuracy.
FAQ
Q1: Why does 985.67 round to 1000 and not 900?
A: Because the tens digit is 8 (≥5), so we round up to the next hundred.
Q2: What happens if the tens digit is exactly 5?
A: Always round up. For example, 950 → 1000.
Q3: Why are zeros added after rounding?
A: Zeros replace the dropped digits and show the new level of precision (in hundreds).
Study Tip
Write down the number line between 900 and 1000. The midpoint is 950. Because 985.67 lies to the right of 950, it’s closer to 1000. Drawing number lines is a great way to visualise rounding decisions and confirm your answers quickly during exams.