You want to find the value of x for which the area under the curve to the left of x is 0.6. One way to do that is to create the cumulative distribution function (CDF) for the given PDF, then see where it is equal to 0.6.
Doing that, we find a = 5.
4 (3n-2) is the answer.
Woops. Sorry I had no idea that it said expression (s) instead of expression, but that is one of the answers though.
Answer: 5/13
Step-by-step explanation:

Answer:
576 students choose cheeseburgers
Step-by-step explanation:
Given: In a survey, it was determined that 40% of students preferred pizza, 32% of students preferred cheeseburgers, and 28% of students preferred tacos.
To find: Number of students out of 1800 who choose cheeseburgers
Solution:
Percentage of students who preferred cheeseburgers = 32%
Total number of students = 1800
Number of students out of 1800 who choose cheeseburgers = 
The manager’s likely error was forgetting to add the $2 back to the $18. Because $2 is roughly 11% of $18 for a markup you need to add the $2 back into the $18 for a total of $20.