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^2+4x-32=0
(mid-term breaking---4 x 8=32)
x^2+8x-4x-32=0
x(x+8)-4(x+8)
x+8=0 or x-4=0
So x=+4 or x=-8
Step-by-step explanation:
Answer:
64
Step-by-step explanation:
Perfect squares are integers multiplied by themselves.
- 2 times 2 = 4
- 3 times 3 = 9
- 4 times 4 = 15
The closest perfect squares to 54 are 49 (7^2) and 64 (8^2).
49 is less than 54, so that's ruled out.
Therefore, the closest perfect square to 54 that is greater than it is 64.
25/45=(5∗5)/(5∗9)=5/9
5/9 is the answer.
Answer: 0.50
Step-by-step explanation:
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