LightMySky

Working with Large Numbers

Solve number and practical problems involving reading, writing, ordering, comparing, and rounding whole numbers up to 1,000,000

No account needed. Progress saves in this browser.

What a learner can do afterwards

  • What is the largest six-digit number with digits summing to 15?
  • A stadium holds 67,450 people. Round to the nearest thousand for a news report
  • Order the populations of five cities and find the difference between the largest and smallest

The lesson

You already know how to read big numbers and round them. Now you will compare numbers to see which is larger, and put a group of numbers in order from smallest to largest.

To compare two big numbers, first count the digits. A number with more digits is always bigger, no matter what those digits are. If the digit counts match, compare digit by digit starting from the left. The first spot where the digits differ decides which number is bigger.

Elmside312450Rivertown298700Oakford320100Millbrook305600
Look at the bars. Which town has the most people, and which has the fewest?
Try it together

To build the biggest six-digit number with digits that add to 15, put as much of that sum as you can into the leftmost digit. Try 9 first: that leaves 6 for the rest, so the next digit can be 6, and the last four digits become 0. The number is 960,000.

Good to know

You already know how to round. Use that skill whenever a big number needs to sound simpler, like turning a stadium crowd of 67,450 into about 67,000 for a headline.

Count the digits first, then compare from the left until you find a difference: that tells you which large number wins.

Watch it

Where it sits

Learn first

This opens up

Nothing builds on it yet.

Where this leads

Jobs that lean on this skill. Follow one to see everything it is built on.

Then practise

8 questions wait behind this lesson, each with its answer explained. Every answer feeds the sky: stars light as they are learned, and dim when it is time to come back.

Working with Large Numbers · Mathematics, ages 9 to 10 · LightMySky