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!
A should be the correct answer. Let me know if I’m right!
Answer:
20m
Step-by-step explanation:
4 x 5 = 20
therefore the 5 benches are 20m long
You would do 40/x=x/15, therefore you get x^2=600. to find x you find the square root of each side. Rounded to the nearest tenth, you get 24.5. If you put it in simplest radical form you should get 10 times the square root of 6
Answer:
<h3>
There is one unique real number solution at (–1, –3)</h3>
Step-by-step explanation:
Given the two linear equation
–4x – 7 = y ...1
x² – 2x – 6 = y ...2
Equating the left hand side of both equations since they are equal to the same variable y will give;
Substituting x=1 into equation 1 we have;
This means there is only one unique real number solution at (-1, -3)
