Introduction to Ordering Decimal Amounts

Hello, Year 4! Today we’re going to learn about ordering decimal amounts. This means putting numbers with decimals in the right order, from the smallest to the largest or vice versa.

What are Decimals?

Decimals are numbers that have a whole part and a fractional part, separated by a dot (or decimal point). For example:

  • 2.5 (two and five tenths)
  • 0.75 (zero and seventy-five hundredths)

Why Order Decimals?

Ordering decimals helps us compare different amounts. It’s useful in many real-life situations, like price comparisons or measuring lengths.

How to Order Decimals

Step 1: Line Up the Decimals

When you’re comparing decimal numbers, it helps to line them up by the decimal point. For example:

   2.34   2.5   2.345

Step 2: Compare the Whole Numbers

First, look at the whole numbers (the part before the decimal point).

  • If they are the same, move to the next step.
  • If they are different, the larger whole number is larger overall.

Step 3: Compare the Decimal Parts

If the whole numbers are the same, look at the first digit after the decimal point. Compare those numbers:

  • If the first digits are the same, move to the second digit.
  • Continue until you find a difference.

Example

Let’s order these decimal numbers: 0.7, 0.65, and 0.8.

  1. Line them up: 0.70 0.65 0.80
  2. Compare the whole numbers (all are 0).
  3. Compare the first digit after the decimal:
    • 7 (from 0.70) is larger than 6 (from 0.65).
    • 8 (from 0.80) is largest.

So, the order is: 0.65, 0.70, 0.80.

Tips and Tricks

  • Always line up the decimal points.
  • Compare one digit at a time from left to right.
  • You can add zeros to the end of a decimal if it helps you compare (like turning 0.7 into 0.70).

Practice Questions

Easy Level Questions

  1. Order these: 0.3, 0.1, 0.2
  2. Order these: 1.5, 1.2, 1.3
  3. Order these: 0.6, 0.4, 0.5
  4. Order these: 2.1, 2.0, 2.2
  5. Order these: 0.9, 0.8, 0.7
  6. Order these: 3.2, 3.1, 3.3
  7. Order these: 4.5, 4.4, 4.6
  8. Order these: 0.05, 0.01, 0.02
  9. Order these: 5.0, 5.1, 5.2
  10. Order these: 0.75, 0.50, 0.25

Medium Level Questions

  1. Order these: 1.45, 1.54, 1.34
  2. Order these: 2.30, 2.3, 2.33
  3. Order these: 0.89, 0.9, 0.08
  4. Order these: 4.7, 4.07, 4.17
  5. Order these: 0.15, 0.25, 0.05
  6. Order these: 3.03, 3.3, 3.33
  7. Order these: 2.22, 2.2, 2.202
  8. Order these: 0.4, 0.44, 0.404
  9. Order these: 1.99, 1.9, 1.909
  10. Order these: 5.55, 5.5, 5.505

Hard Level Questions

  1. Order these: 3.141, 3.14, 3.1415
  2. Order these: 2.718, 2.7, 2.7182
  3. Order these: 0.999, 0.99, 0.9
  4. Order these: 4.567, 4.56, 4.5678
  5. Order these: 1.2345, 1.23, 1.234
  6. Order these: 0.123, 0.12, 0.1234
  7. Order these: 6.5, 6.50, 6.5001
  8. Order these: 2.345, 2.34, 2.3456
  9. Order these: 0.001, 0.01, 0.1
  10. Order these: 7.89, 7.9, 7.899

Answers

Easy Level Answers

  1. 0.1, 0.2, 0.3
  2. 1.2, 1.3, 1.5
  3. 0.4, 0.5, 0.6
  4. 2.0, 2.1, 2.2
  5. 0.7, 0.8, 0.9
  6. 3.1, 3.2, 3.3
  7. 4.4, 4.5, 4.6
  8. 0.01, 0.02, 0.05
  9. 5.0, 5.1, 5.2
  10. 0.25, 0.50, 0.75

Medium Level Answers

  1. 1.34, 1.45, 1.54
  2. 2.3, 2.30, 2.33
  3. 0.08, 0.89, 0.9
  4. 4.07, 4.17, 4.7
  5. 0.05, 0.15, 0.25
  6. 3.03, 3.3, 3.33
  7. 2.2, 2.202, 2.22
  8. 0.4, 0.404, 0.44
  9. 1.9, 1.909, 1.99
  10. 5.505, 5.5, 5.55

Hard Level Answers

  1. 3.14, 3.141, 3.1415
  2. 2.7, 2.718, 2.7182
  3. 0.9, 0.99, 0.999
  4. 4.56, 4.567, 4.5678
  5. 1.23, 1.234, 1.2345
  6. 0.12, 0.123, 0.1234
  7. 6.5, 6.50, 6.5001
  8. 2.34, 2.345, 2.3456
  9. 0.001, 0.01, 0.1
  10. 7.89, 7.899, 7.9