120,117 views
3 votes
3 votes
Can someone help me with this? I don't know what i'm supposed to do.

Can someone help me with this? I don't know what i'm supposed to do.-example-1
User JTY
by
2.7k points

1 Answer

27 votes
27 votes

Answer:

A) attached

B) 15/36 = 5/12

C) 21/36 = 7/12

D) 18/36 = 1/2

E) 32/36 = 8/9

Explanation:

A probability distribution is a table showing all the possible values a discrete random variable can take, plus the probability that it'll take each value.

Let X be the score of a pair of fair six-sided dice

X can take the values 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 and 12

Create a sample space (attached) to visually see the sums of different combinations and to help construct the probability distribution table (attached)

B) Reading from the table:

P(X ≥ 8) = P(X=8) + P(X=9) + P(X=10) + P(X=11) + P(X=12)

= 5/36 + 4/36 + 3/36 + 2/36 + 1/36

= 15/36 = 5/12

C) Reading from the table:

P(X ≤ 7) = P(X=7) + P(X=6) + P(X=5) + P(X=4) + P(X=3) + P(X=2)

= 6/36 + 5/36 + 4/36 + 3/36 + 2/36 + 1/36

= 21/36 = 7/12

D) Reading from the table:

P(X is even) = P(X=2) + P(X=4) + P(X=6) + P(X=8) + P(X=10) + P(X=12)

= 1/36 + 3/36 + 5/36 + 5/36 + 3/36 + 1/36

= 18/36 = 1/2

E) Reading from the table:

P(3≤X≤10) = P(X=3) + P(X=4) + P(X=5) + P(X=6) + P(X=7) + P(X=8) +

P(X=9) + P(X=10)

= 2/36 + 3/36 + 4/36 + 5/36 +6/36 + 5/36 + 4/36 + 3/36

= 32/36 = 8/9

Can someone help me with this? I don't know what i'm supposed to do.-example-1
Can someone help me with this? I don't know what i'm supposed to do.-example-2
User Danilo Puric
by
2.8k points