Answer:
.3
Step-by-step explanation:
A|B (A given b)= (A and b)/b
so
Sore throat|Fever= sore throatand fever/fever
.21/.7= .3
10099 is this right i think it would be
Answer:
31.25% probability that the Blair family had at least 3 girls
Step-by-step explanation:
For each children, there are only two possible outcomes. Either it was a girl, or it was not. The probability of a child being a girl is independent of any other children. So we use the binomial probability distribution to solve this question.
Binomial probability distribution
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.

In which
is the number of different combinations of x objects from a set of n elements, given by the following formula.

And p is the probability of X happening.
They had 4 children.
This means that 
The probability of a child being a girl is 0.5
This means that 
Probability of at least 3 children:





31.25% probability that the Blair family had at least 3 girls
14x + 11y = 896
x = number of adults
y= number of kids
if nine adults went then 70 kids went
I can’t really see it well