C Curriculum Explorer
Mathematics·Probability·conceptual

The 0-to-1 Probability Scale

Understand probability as a measure expressed as a number between 0 (impossible) and 1 (certain); place events on the probability scale; express probabilities as fractions, decimals, and percentages

Suggested ages 10–11

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Evidence of understanding

  • Place events on a number line from 0 (impossible) to 1 (certain), expressing positions as fractions or decimals
  • Explain that a probability of 0.5 means 'even chance' and connect this to the informal word 'likely'
  • Convert between informal language ('very unlikely') and a numerical position on the 0-to-1 scale

Assessment prompt

Can The 0-to-1 Probability Scale write the same probability as a fraction, a decimal, and a percentage — for example, knowing that an even chance is ½, 0.5, and 50%?

Standards alignment

No external standards are linked to this topic.