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:
x
^15
Step-by-step explanation:
C because you got to find the like term term
Answer:
its 3
Step-by-step explanation:
Simplifying
8 = 3x + -1
Reorder the terms:
8 = -1 + 3x
Solving
8 = -1 + 3x
Solving for variable 'x'.
Move all terms containing x to the left, all other terms to the right.
Add '-3x' to each side of the equation.
8 + -3x = -1 + 3x + -3x
Combine like terms: 3x + -3x = 0
8 + -3x = -1 + 0
8 + -3x = -1
Add '-8' to each side of the equation.
8 + -8 + -3x = -1 + -8
Combine like terms: 8 + -8 = 0
0 + -3x = -1 + -8
-3x = -1 + -8
Combine like terms: -1 + -8 = -9
-3x = -9
Divide each side by '-3'.
x = 3
Simplifying
x = 3 this took forever to type hope it helped
