Answer:
f’(x) = x -2/7
Step-by-step explanation:
Let f(x)= y
Thus;
y = x + 2/7
x = y-2/7
So the inverse f’(x) = x - 2/7
6.75 X 10 to the tenth power
Answer: $10
Step-by-step explanation:
Assume the price of the phone case is x.
Assume the price of the charging cord is y.
Discounted price for phone case : 15% * x
= 0.15x
Discounted price for charging cord = 0.15y
Expression is therefore:
0.15x + 0.15y = 4.20
0.15 * 18 + 0.15y = 4.20
2.7 + 0.15y = 4.20
0.15y = 4.2 - 2.7
y = 1.5/0.15
y = $10

a. 9:00 AM is the 60 minute mark:

b. 8:15 and 8:30 AM are the 15 and 30 minute marks, respectively. The probability of arriving at some point between them is

c. The probability of arriving on any given day before 8:40 AM (the 40 minute mark) is

The probability of doing so for at least 2 of 5 days is

i.e. you're virtually guaranteed to arrive within the first 40 minutes at least twice.
d. Integrate the PDF to obtain the CDF:

Then the desired probability is
