Answer:
a) 
b) 
Step-by-step explanation:
From the question we are told that:
3 coin are tossed
Therefore
Sample space 
Generally the sets that correspond with the result of at most one tail is therefore given as follows

Therefore
The result is at most one tail when

Answer:
This is verry easy! Is 105.56,do u need expabation?
Answer:
2500
Step-by-step explanation:
Given:
The race percent of population is
White: 45%
Hispanic: 27%
Black: 18%
Asian: 7%
Other: 3%
Part a.
The university has 2,815 Hispanic out of the 20,250 total population.
This is equivalent to (2815/20250)*100 = 13.9%
This percentage is less than 27%, so Hispanics do not have proportional representation.
Answer: The Hispanic students do not have proportional representation.
Part b.
Let x = the extra number of Hispanic students needed for proportional representation of 27% or 0.27.
Then
(2815 + x)/20250 = 0.27
2815 + x = 20250*0.27 = 5467.5
x = 5467.5 - 2815 = 2652.5
This means that 2,653 extra Hispanic students are required for a population of 20,250 students.
Answer: 2,653 extra Hispanic students.