tree diagram

Definition of Tree Diagram

  • A tree diagram shows all the possible outcomes of an event.
  • All possible outcomes of an event are shown by a tree diagram.

Examples of Tree Diagram

  • If a coin is tossed and the number cube is rolled simultaneously then the probability of getting head on the coin and the number 4 on the number cube is .

  • If two coins are tossed simultaneously then the possible outcomes are 4. The possible outcomes are HH, HT, TH, TT. The tree diagram below shows the possible outcomes.

Solved Example on Tree Diagram

A box has 1 red ball, 1 green ball and 1 blue ball, 2 balls are drawn from the box one after the other, without replacing the first ball drawn. Use the tree diagram to find the number of possible outcomes for the experiment. 

A. 2
B. 4
C. 6
D. 3
Correct Answer: C
Step 1: The possible outcomes are RG, RB, GR, GB, BG, and BR. 
Step 2: So, the number of possible outcomes is 6.

Related Terms for Tree Diagram

  • Probability
  • Outcome
  • Event