Ages 10–11🧮 Mathematics9 verified questions on this shelf
Probabilities Sum to One
Understand that when all possible outcomes of a trial are listed, their probabilities must add up to 1; use this to find the probability of an event NOT happening: P(not A) = 1 − P(A); apply this shortcut to avoid counting all unfavourable…
Try three questions
Tap an answer to check it. Every question and explanation was checked by independent verifiers that must agree.
Question 1 of 3
A spinner is divided into four equal sections colored red, blue, green, and yellow. If the spinner is spun once, which list correctly shows all possible outcomes with their probabilities and adds up to 1?
Question 2 of 3
A game board has a circular spinner divided into four equal sections labeled A, B, C, and D. Each section is equally likely to be landed on when the spinner is spun once. Which of the following lists all possible outcomes with their correct probabilities and also shows that the total probability equals 1?
Question 3 of 3
A standard six‑sided die is rolled once. What is the probability of NOT rolling a 3?
Keep going on this shelf
A free account keeps practising Probabilities Sum to One with 9 verified questions, tracks the Skill as it blooms, and connects a real teacher when you want one. Every student account needs a parent's email first.