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
Answer:
Option C. 1,024 bacteria
Step-by-step explanation:
We are given that a bacteria culture begins with 4 bacteria which double in size every hour. And we have to find that how many bacteria exist in the culture after 8 hours;
So, Number of bacteria after one hour = 4 * 2 = 8
Number of bacteria after two hours = 8 * 2 = 16
Number of bacteria after three hours = 16 * 2 = 32
Number of bacteria after four hours = 32 * 2 = 64
Number of bacteria after five hours = 64 * 2 = 128
Number of bacteria after six hours = 128 * 2 = 256
Number of bacteria after seven hours = 256 * 2 = 512
Number of bacteria after eight hours = 512 * 2 = 1,024
Therefore, 1,024 bacteria exist in the culture after 8 hours .
Answer:
It would take him approximately 16.62 minutes to reach the bookstore
Step-by-step explanation:
Total steps to the bookstore=Number of steps per minute×number of minutes
where;
Total steps to the bookstore=864 steps
Number of steps per minute=52
Number of minutes=t
Replacing;
864=52×t
t=864/52
t=16.62 minutes
It would take him approximately 16.62 minutes to reach the bookstore
Answer:x=8/5 or 1.6
Step-by-step explanation:
