Equally Likely Outcomes · seed 1 · A4, ink-friendly. The answer key prints on its own page for grown-ups.

Equally likely outcomes

Mathematics · Probability · ages 9-10
Name ______________________   Date ____________

  1. A spinner has four equal sections, two blue and two yellow. Blue and yellow are equally likely colours.

    Circle one:   True   False

  2. A spinner has four equal sections: two red, one blue, and one green. Are the three colours equally likely?

    • No, red covers two of the four sections
    • Yes, every colour has one chance
    • Yes, four sections always give equal colours
    • No, blue is impossible

  3. A fair coin is flipped. Are heads and tails equally likely?

    • Yes, equally likely
    • No, heads is more likely
    • No, tails is more likely

  4. A fair die has 6 faces, and each face has the same chance of landing face up.

    Circle one:   True   False

  5. A bag has 4 green counters and 2 purple counters. Green and purple are equally likely colours.

    Circle one:   True   False

  6. A bag has 3 red, 3 blue, and 1 green counter. Which statement is true?

    • All three colours are equally likely
    • Red and blue are equally likely, but green is less likely
    • Green is more likely than red
    • Only green is equally likely

  7. A spinner has four equal sections: three blue and one green. Which colour is more likely?

    • Green
    • Blue
    • Both colours are equal
    • Neither colour

  8. Bag A has 2 red and 2 blue counters. Bag B has 5 red and 1 blue counter. Which bag has equally likely outcomes?

    A Red2A Blue2B Red5B Blue1
    • Bag B
    • Bag A
    • Both bags

  9. Ben says: 'A spinner with 3 sections is always equally likely, no matter the size of each section.' What is wrong with Ben's idea?

    • He is right, sections are always equal
    • He should count colours instead of sections
    • He is only counting sections, not comparing their sizes

  10. A spinner has six equal sections: three red, two blue, and one yellow. Landing on red is exactly as likely as landing on blue or yellow, with blue and yellow counted together.

    Circle one:   True   False

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Answer key

For grown-ups. Fold this page away before handing over the rest.

Equally likely outcomes W1-mt_xSgAgg9Ej_-s1

  1. True · Blue and yellow each cover two of the four equal sections.
  2. No, red covers two of the four sections · Red covers two of the four equal sections, so red is more likely than blue or green.
  3. Yes, equally likely · A fair coin gives heads and tails the same chance of landing face up, so they are equally likely.
  4. True · A standard die has 6 faces of the same size, so each number 1 through 6 has the same chance.
  5. False · Green has 4 counters and purple has only 2. Different amounts give different chances, so green is more likely than purple.
  6. Red and blue are equally likely, but green is less likely · Red and blue each have 3 counters. Green has only 1, so it has a smaller chance.
  7. Blue · Blue covers three of the four equal sections, so blue is more likely.
  8. Bag A · Bag A has the same number of red and blue counters, so it is equally likely. Bag B has more red than blue, so it is not.
  9. He is only counting sections, not comparing their sizes · Counting sections is not enough. If the sections are different sizes, some outcomes are more likely than others.
  10. True · Red covers 3 equal sections. Blue and yellow together cover 2 + 1 = 3 equal sections. Matching section counts give matching chances, so the statement is true.
Worksheet · LightMySky