Example 1: What is the likelihood of choosing a day that falls on the weekend when randomly picking a day of the week? “Choosing a day that falls on the weekend” is our event, and the number of outcomes is the total number of days in a week: 7. Example 2: A jar contains 4 blue marbles, 5 red marbles and 11 white marbles. If a marble is drawn from the jar at random, what is the probability that this marble is red? “Choosing a red marble” is our event, and the number of outcomes is the total number of marbles in the jar, 20.
Example 1: What is the likelihood of choosing a day that falls on the weekend when randomly picking a day of the week? The number of events is 2 (since 2 days out of the week are weekends), and the number of outcomes is 7. The probability is 2 ÷ 7 = 2/7. You could also express this as 0. 285 or 28. 5%. Example 2: A jar contains 4 blue marbles, 5 red marbles and 11 white marbles. If a marble is drawn from the jar at random, what is the probability that this marble is red? The number of events is 5 (since there are 5 red marbles), and the number of outcomes is 20. The probability is 5 ÷ 20 = 1/4. You could also express this as 0. 25 or 25%.
For example, the likelihood of rolling a 3 on a 6-sided die is 1/6. But the probability of rolling all five other numbers on a die is also 1/6. 1/6 + 1/6 + 1/6 + 1/6 + 1/6 + 1/6 = 6/6 , which = 100%.
For example, if you were to calculate the probability of the Easter holiday falling on a Monday in the year 2020, the probability would be 0 because Easter is always on a Sunday.
Example 1: Consider the event: Two cards are drawn randomly from a deck of cards. What is the likelihood that both cards are clubs? The likelihood that the first card is a club is 13/52, or 1/4. (There are 13 clubs in every deck of cards. ) Now, the likelihood that the second card is a club is 12/51, since 1 club will have already been removed. This is because what you do the first time affects the second. If you draw a 3 of clubs and don’t put it back, there will be one less club and one less card in the deck (51 instead of 52). Example 2: A jar contains 4 blue marbles, 5 red marbles, and 11 white marbles. If 3 marbles are drawn from the jar at random, what is the probability that the first marble is red, the second marble is blue, and the third is white? The probability that the first marble is red is 5/20, or 1/4. The probability of the second marble being blue is 4/19, since we have 1 less marble, but not 1 less blue marble. And the probability that the third marble is white is 11/18, because we’ve already chosen 2 marbles.
Now, the likelihood that the second card is a club is 12/51, since 1 club will have already been removed. This is because what you do the first time affects the second. If you draw a 3 of clubs and don’t put it back, there will be one less club and one less card in the deck (51 instead of 52).
The probability that the first marble is red is 5/20, or 1/4. The probability of the second marble being blue is 4/19, since we have 1 less marble, but not 1 less blue marble. And the probability that the third marble is white is 11/18, because we’ve already chosen 2 marbles.
Example 1: Two cards are drawn randomly from a deck of cards. What is the likelihood that both cards are clubs? The probability of the first event happening is 13/52. The probability of the second event happening is 12/51. The probability is 13/52 x 12/51 = 12/204 = 1/17. You could also express this as 0. 058 or 5. 8%. Example 2: A jar contains 4 blue marbles, 5 red marbles and 11 white marbles. If three marbles are drawn from the jar at random, what is the probability that the first marble is red, the second marble is blue, and the third is white? The probability of the first event is 5/20. The probability of the second event is 4/19. And the probability of the third event is 11/18. The probability is 5/20 x 4/19 x 11/18 = 44/1368 = 0. 032. You could also express this as 3. 2%.
The number 11 represents the likelihood of choosing a white marble and the number 9 represents the likelihood of choosing a marble of a different color. So, odds are that you will draw a white marble.
The event that you’ll draw a white marble is 11; the event another color will be drawn is 9. The total number of outcomes is 11 + 9, or 20.
So, in our example, the probability of drawing a white marble is 11/20. Divide this out: 11 ÷ 20 = 0. 55 or 55%.