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!
The correct answer would be letter C. She needs to either break or tie the record. The less than or equal to symbol in the original inequality would be her scoring less or tying the record. Using the greater than or equal to sign would represent her breaking the record or tying with it. Hope this helped.
Cheetah travels 0.15 km in .....................5 seconds or
15000 cm ......................5 seconds
a snail travels 1.5 cm in ...........................5 seconds
the cheetah travels in 5 seconds 15000-1.5=14998.50 cm which is equal to
149.985 meters which is choice A