Normal distributon problems – assume that the mean hourly cost to



1. Assume that the medium hourly absorb to have-effect a commercial airplane prospers the typical arrangement delay a medium of $2,075 per hour and a rule irregularity of $225.

What is the untrammelled absorb for the mediumest 6 percent of the airplanes? (Round z appreciate to 2 decimal locates. Omit the "$" premonition in your defense.)

Operating Costs $

2.The absorb per part at a supermarket prospers an exponential arrangement. There are sundry worthless parts and a few relatively valuable ones. The medium absorb per part is $6.00. What is the percentage of parts that absorb:

rev: 10_13_2011
(a) Less than $3.00? (Round your defense to 4 decimal locates.)

Probability

 

3. A unvarying arrangement is defined aggravate the balancetime from 6 to 10.

(a) What are the appreciates for a and b?

a

b

________________________________________

(b) What is the medium of this unvarying arrangement?

Mean


(c) What is the rule irregularity? (Round your defense to 2 decimal locates.)

Standard irregularity


(d) The entirety area is 1.00.


(e) Find the likelihood of a appreciate past than 7. (Round your defense to 2 decimal locates.)

Probability


(f) Find the likelihood of a appreciate among 7 and 9. (Round your defense to 1 decimal locate.)

Probability


4. The medium of a typical likelihood arrangement is 60; the rule irregularity is 5. (Round your defenses to 2 decimal locates. Omit the % premonition in your defense.)

(a) About what percent of the observations lie among 55 and 65?

Percentage of observations %


(b) About what percent of the observations lie among 50 and 70?

Percentage of observations %


(c) About what percent of the observations lie among 45 and 75?

Percentage of observations %


7. The solution for a one-bedroom berth in Southern California prospers the typical arrangement delay a medium of $2,300 per month and a rule irregularity of $220 per month. The arrangement of the monthly absorbs does not prosper the typical arrangement. In occurrence, it is positively skewed.

What is the likelihood of selecting a specimen of 70 one-bedroom berths and exculpation the medium to be at last $2,250 per month? (Round z appreciate to 2 decimal locates and terminal defense to 4 decimal locates.)

9 Scrapper Elevator Company has 20 sales figuratives who vend their work throughout the United States and Canada. The reckon of units sold by each figurative is listed beneath. Assume these sales figures to be the population appreciates.

2 3 2 3 3 4 2 4 3 2 2 7 3 4 5 3 3 3 3 5

Compute the Medium of the population (plump to 1 decimal locate)

10 What is the premonition for rule blunder of the medium?