Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

Use the empirical rule to solve the problem. 3) The lifetimes of lightbulbs of a

ID: 2951603 • Letter: U

Question

Use the empirical rule to solve the problem.
3) The lifetimes of lightbulbs of a particular type are normallydistributed with a mean of 290 hours
and a standard deviation of 6 hours. What percentage of the bulbshave lifetimes that lie within 1
standard deviation to either side of the mean?
A) 68.26% B) 31.74% C) 84.13% D) 95.44%
4) The amount of Jen's monthly phone bill is normally distributedwith a mean of $53 and a standard
deviation of $10. What percentage of her phone bills are between$23 and $83?
A) 99.99% B) 99.74% C) 95.44% D) 68.26%

Explanation / Answer

3. A 68.26% 4. B 99.74% -- Just remember the 68-95-99.7 rule
Hire Me For All Your Tutoring Needs
Integrity-first tutoring: clear explanations, guidance, and feedback.
Drop an Email at
drjack9650@gmail.com
Chat Now And Get Quote