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 and step-by-step explanation:
We learn that (a+b)^3 = a^3 + 3a^2b + 3ab^2 + b^3
So in this case, it would be:
= x^3 + (3*x^2*2) + (3*x*2^2) + 2^3
= x^3 + 6x^2 + 3x * 4 + 8
= x^3 + 6x^2 + 12x + 8
This is the standard form of the equation
Hope it help you :3
