Three unbiased dice are thrown simultaneously. What is the probability...
When three unbiased dice are thrown, there are 63 = 216 combinations possible.
The least possible sum is 3 and the highest possible sum is 18.
The multiples of 4 in this range are 4, 8, 12 and 16
Sum = 4:
Obtained for the combination (1,1, 2).
This combination can be made in 3!/2! = 3 ways
Sum = 8:
Obtained for the combinations-
(1, 1,6)- possible in 3!/2! = 3 ways
(1,2, 5) - possible in 3! = 6 ways
(1, 3, 4) - possible in 3! = 6 ways
(2, 2, 4) - possible in 3!/2! = 3 ways
(2, 3, 3) - possible in 3!/2! = 3 ways
Total number of ways = 3 + 6 + 6 + 3 + 3 = 21
Sum = 12:
Obtained for the combinations-
(1, 5, 6) - possible in 3! = 6 ways
(2, 4, 6) - possible in 3! = 6 ways
(2, 5, 5) - possible in 3!/2! = 3 ways
(3, 3, 6) - possible in 3!/2! = 3 ways
(3, 4, 5) - possible in 3! = 6 ways
(4, 4, 4) - possible in 1 way
Total number of ways = 6 + 6 + 3 + 3 + 6 + 1 =25
Sum = 16:
Obtained for the combinations-
(4, 6, 6) - possible in 3!/2! = 3 ways
(5, 5, 6) - possible in 3!/2! = 3 ways
Total number of ways = 3 + 3 = 6
Overall total unmber of ways = 3 + 21 + 25 + 6 = 55
Required probability = 55/216 = 0.254 Hence, option 1.
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Three unbiased dice are thrown simultaneously. What is the probability...
Introduction:
We are given three unbiased dice and we need to find the probability that the sum of the three numbers on them is divisible by 4. To solve this problem, we can use the concept of probability and combinatorics.
Approach:
To find the probability, we need to determine the favorable outcomes and the total possible outcomes.
Favorable outcomes:
For the sum to be divisible by 4, we need to consider the possible combinations of numbers on the three dice that add up to a multiple of 4. Let's list down all the possible outcomes:
- (1,1,2)
- (1,2,1)
- (2,1,1)
- (2,2,2)
- (1,1,6)
- (1,6,1)
- (6,1,1)
- (2,2,6)
- (2,6,2)
- (6,2,2)
- (3,3,4)
- (3,4,3)
- (4,3,3)
- (4,4,4)
- (3,3,8)
- (3,8,3)
- (8,3,3)
- (4,4,8)
- (4,8,4)
- (8,4,4)
- (5,5,6)
- (5,6,5)
- (6,5,5)
- (5,5,10)
- (5,10,5)
- (10,5,5)
- (6,6,8)
- (6,8,6)
- (8,6,6)
- (7,7,10)
- (7,10,7)
- (10,7,7)
- (8,8,8)
- (7,7,12)
- (7,12,7)
- (12,7,7)
- (8,8,12)
- (8,12,8)
- (12,8,8)
- (9,9,12)
- (9,12,9)
- (12,9,9)
- (10,10,12)
- (10,12,10)
- (12,10,10)
- (11,11,12)
- (11,12,11)
- (12,11,11)
- (12,12,12)
Therefore, there are 45 favorable outcomes.
Total possible outcomes:
Since each dice has 6 faces, the total possible outcomes for the three dice can be calculated as 6 * 6 * 6 = 216.
Probability:
The probability is given by the ratio of favorable outcomes to total possible outcomes.
Probability = Favorable outcomes / Total possible outcomes
Probability = 45 / 216
Probability = 0.208
Therefore, the probability that the sum of the three numbers on the dice is divisible by 4 is approximately 0.208.
Conclusion:
The probability that the sum of the numbers on the three unbiased dice is divisible by 4 is approximately 0.208.