Answer:
1/4
Step-by-step explanation:
Let's denote the probabilities as following:
Probability that a teenager has a sister:
P(A) = 12/28
Probability that a teenager has a brother:
P(B) = 7/28
Probability that a teenager has both a sister and a brother:
P(A⋂B) = 3/28
Probability that a selected teenager has a sister also has a brother, or in other words, he/she has a brother, given he/she had a sister:
P(B|A)
Let's apply the formula of conditional probability to work out P(B|A)
P(B|A) = P(A⋂B)/P(A) = (3/28)/(12/28) = (3*28)/(12*28) = 3/12 = 1/4
=> Option C is correct
Hope this helps!
Answer:
88
Step-by-step explanation:
12.5% is the same as 1/8 of something
11*8=88
I believe the correct answer from the choices listed above is option B. The solution to a system of inequalities is <span>a collection of points that satisfy all inequalities in the system. It will always be a number of points that will agree with the inequality.</span>
Hope this answers the question. Have a nice day.
Answer:
a= 2x <u><em>(edit: i just forgot it should be a integer x.x, forgive my blondiness)</em></u>
Step-by-step explanation:
usually when doing equations like that, you can separate one of the parenthesis with 0
(in this case, we will use (2x-a) )
Then create a equation, which should look like:
2x-a=0
Then solve for a

Answer:
the expected value of this raffle if you buy 1 ticket = -0.65
Step-by-step explanation:
Given that :
Five thousand tickets are sold at $1 each for a charity raffle
Tickets are to be drawn at random and monetary prizes awarded as follows: 1 prize of $500, 3 prizes of $300, 5 prizes of $50, and 20 prizes of $5.
Thus; the amount and the corresponding probability can be computed as:
Amount Probability
$500 -$1 = $499 1/5000
$300 -$1 = $299 3/5000
$50 - $1 = $49 5/5000
$5 - $1 = $4 20/5000
-$1 1- 29/5000 = 4971/5000
The expected value of the raffle if 1 ticket is being bought is as follows:





Thus; the expected value of this raffle if you buy 1 ticket = -0.65