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
You would have to solve for x the plug in the answer for c into the next equation to find your answer
The amount of decrease is $12.00 :$72.00 - $60.00 = $12.00
you then divide the amount of decrease by the original price to find the percent decrease:
$12.00 ÷ $72.00 = .166666... = 16.7%
