College Statistics Quiz
20 questions · no time limit
0:00
PROBABILITY FOUNDATIONS
Question 1 of 20
No time limit
Current
Answered
Flagged
Not seen
The lifetime of a smartphone battery is normally distributed with a mean of 400 hours of use and a standard deviation of 25 hours. The manufacturer wishes to offer a warranty, replacing any battery that fails before a guaranteed time T. If the company is willing to replace no more than 2.5% of its batteries, what is the maximum number of hours T they can guarantee, rounded to the nearest hour?
YOUR PROGRESS
20
QUESTIONS
Ready when you are
Answer in any order. Your progress shows here as you go.
QUESTIONS
KEYBOARD
Pick an answer ABCD
Next question ↵→
Previous ←
Flag for review F
Answers save as you go · flagged questions come back at the end