What decimal number is illustrated?

key notes:

Understanding Decimals
  • A decimal number is a way to represent fractions and whole numbers together using a decimal point.
  • The position of each digit in a decimal number indicates its value (place value).
Place Value in Decimals

Digits to the left of the decimal point represent whole numbers (e.g., ones, tens, hundreds).

Digits to the right of the decimal point represent fractional parts:

  • Tenths (1/10): First place after the decimal.
  • Hundredths (1/100): Second place after the decimal.
  • Thousandths (1/1000): Third place after the decimal.
Visualizing Decimals

Grids:

  • A 10×10 grid represents 1 unit divided into 100 equal parts (hundredths).
  • Example: If 45 squares are shaded, the decimal is 0.45 (45/100).

Number Lines:

  • Decimals are placed between whole numbers.
  • Example: On a number line from 0 to 1, the point halfway represents 0.5.
Interpreting Decimal Representations

Shaded Figures: Count the shaded parts and divide by the total parts to determine the decimal.

  • Example: In a circle divided into 10 equal parts with 7 shaded, the decimal is 0.7.

Bar Models: Identify the fraction of the bar shaded and convert it to a decimal.

  • Example: A bar divided into 5 parts with 3 shaded represents 0.6 (3/5 = 0.6).
Converting Decimals to Fractions

Write the decimal as a fraction and simplify if needed.

  • Example: 0.75 = 75/100 = 3/4.
Common Decimal Equivalents
  • 1/2 = 0.5
  • 1/4 = 0.25
  • 3/4 = 0.75
  • 1/10 = 0.1
Real-Life Applications

Understanding decimals is essential for money calculations, measurements, and data interpretation.

Activities to Practice
  • Identify the decimal represented by shaded parts of a grid or figure.
  • Place decimal numbers correctly on a number line.
  • Convert fractions from visual representations into decimals.
Examples:
  1. Grid Example:
    A grid with 100 squares has 62 shaded. The decimal is 0.62.
  2. Number Line Example:
    A point halfway between 1 and 2 on a number line is 1.5.
  3. Shaded Circle Example:
    A circle divided into 10 parts with 3 shaded is 0.3.

Learn with an example

What decimal number is illustrated?

There are 100 squares. There are 22 colored squares. This picture shows twenty-two hundredths.

Now write twenty-two hundredths as a decimal. Use a place value chart.

ones tenthshundredths
0.22

The answer is 0.22.

What decimal number is illustrated?

There are 100 squares. There are 62 colored squares. This picture shows sixty-two hundredths.

Now write sixty-two hundredths as a decimal. Use a place value chart.

The answer is 0.62.

What decimal number is illustrated?

There are 100 squares. There are 96 coloured squares. This picture shows ninety-six hundredths.

Now write ninety-six hundredths as a decimal. Use a place value chart.

The answer is 0.96.

let’s practice: