is this correct?
1.a jar contains 5 white, 15 violet,and 21 blue marbles. a marble is drawn at random. P(violet or white)
answer: 5x15x21= 1575
15x5=75
75/1575= 1/21
2. a number from 10 to 16 is drawn at random. P(a number greater than 14)
answer: 2/7
P(violet or white)=(5+15)/(5+15+21)
2. YOu have 7 choices (10, 11, 12, ..16)
of those, 15 and 16 are >14
Pr(greater than 14)=2/7
24 don't know
Let's go through each question and explain how to get the answers:
1. The jar contains 5 white marbles, 15 violet marbles, and 21 blue marbles. The probability of drawing a violet or white marble can be found using the formula: P(A or B) = P(A) + P(B) - P(A and B), where A and B are events.
In this case, event A is drawing a violet marble and event B is drawing a white marble. To find the probabilities of events A and B, divide the number of desired outcomes by the total number of possible outcomes.
P(A) = Number of violet marbles / Total number of marbles = 15 / (5 + 15 + 21) = 15 / 41
P(B) = Number of white marbles / Total number of marbles = 5 / (5 + 15 + 21) = 5 / 41
To find P(violet or white), we need to consider the possibility of drawing both a violet and a white marble. However, there are no marbles that are both violet and white in this case, so P(A and B) = 0.
P(violet or white) = P(A) + P(B) - P(A and B) = 15/41 + 5/41 - 0 = 20/41 ≈ 0.4878 or approximately 48.78%
Therefore, the given answer of 1/21 (approximately 0.0476 or approximately 4.76%) is incorrect.
2. A number is drawn randomly from the range 10 to 16. The probability of drawing a number greater than 14 can be found by calculating the number of favorable outcomes (numbers greater than 14) divided by the total number of possible outcomes (the range from 10 to 16, inclusive).
The numbers greater than 14 within the given range are 15 and 16.
Number of favorable outcomes = 2
Total number of possible outcomes = 7 (numbers 10, 11, 12, 13, 14, 15, and 16)
P(a number greater than 14) = Number of favorable outcomes / Total number of possible outcomes = 2/7
Therefore, the given answer of 2/7 is correct.