Question

4. It is claimed that 90% of express mail within the same city is delivered within...

4. It is claimed that 90% of express mail within the same city is delivered within 3 working days of the time of mailing. Ten letters are randomly sent to different locations.

• What is the probability that at least two letters arrive within 3 days?

• Find the mean and the standard deviation of the number of letters that will arrive after 3 days.

Homework Answers

Answer #1

A)

probability that at least two letters arrive within 3 days ,

b)

probability of getting letter after 3 days is q=1-p = 1-0.9 = 0.1

mean = n*q=10*0.1=1

standard deviation = == 0.94868

Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
The US Postal Service reports 88% of first-class mail within the same city is delivered within...
The US Postal Service reports 88% of first-class mail within the same city is delivered within 1 day of the time of mailing. Five letters are randomly send to different local addresses. What is the probability that: a.) All five arrive within 1 day b.) Exactly 4 arrive within 1 day
A certain company sends 40% of its overnight mail parcels via express mail service E1. Of...
A certain company sends 40% of its overnight mail parcels via express mail service E1. Of these parcels, 2% arrive after the guaranteed delivery time (denote the event late delivery by L). Suppose that 50% of the overnight parcels are sent via express mail service E2 and the remaining 10% are sent via E3. Of those sent via E2 on 5% arrive late, whereas 1% of the parcels handled by E3 arrive late. Part a: Draw a tree diagram for...
The postal service sorts mail as Priority Mail Express, Priority Mail, First-Class Mail, or Standard Mail....
The postal service sorts mail as Priority Mail Express, Priority Mail, First-Class Mail, or Standard Mail. Over a period of 3 weeks, 18 of each type were mailed from the Network Distribution Center in Atlanta, Georgia, to Des Moines, Iowa. The total delivery time in days was recorded. Minitab was used to perform the ANOVA. The results follow: Source DF SS MS F P Factor 3 1.30 0.43 1.79 0.157 Error 68 16.45 0.24 Total 71 17.75 Level N Mean...
The postal service sorts mail as Priority Mail Express, Priority Mail, First-Class Mail, or Standard Mail....
The postal service sorts mail as Priority Mail Express, Priority Mail, First-Class Mail, or Standard Mail. Over a period of 3 weeks, 18 of each type were mailed from the Network Distribution Center in Atlanta, Georgia, to Des Moines, Iowa. The total delivery time in days was recorded. Minitab was used to perform the ANOVA. The results follow: Source DF SS MS F P Factor 3 4.19 1.40 6.36 0.001 Error 68 14.66 0.22 Total 71 18.85 Level N Mean...
The postal service sorts mail as Priority Mail Express, Priority Mail, First-Class Mail, or Standard Mail....
The postal service sorts mail as Priority Mail Express, Priority Mail, First-Class Mail, or Standard Mail. Over a period of 3 weeks, 18 of each type were mailed from the Network Distribution Center in Atlanta, Georgia, to Des Moines, Iowa. The total delivery time in days was recorded. Minitab was used to perform the ANOVA. The results follow: Source DF SS MS F P Factor 3 1.30 0.43 1.79 0.157 Error 68 16.45 0.24 Total 71 17.75 Level N Mean...
The postal service sorts mail as Priority Mail Express, Priority Mail, First-Class Mail, or Standard Mail....
The postal service sorts mail as Priority Mail Express, Priority Mail, First-Class Mail, or Standard Mail. Over a period of 3 weeks, 18 of each type were mailed from the Network Distribution Center in Atlanta, Georgia, to Des Moines, Iowa. The total delivery time in days was recorded. Minitab was used to perform the ANOVA. The results follow: Source   DF      SS   MS   F   P Factor   3      2.41   0.80   2.50   0.067 Error   68      21.58   0.32         Total  ...
The postal service sorts mail as Priority Mail Express, Priority Mail, First-Class Mail, or Standard Mail....
The postal service sorts mail as Priority Mail Express, Priority Mail, First-Class Mail, or Standard Mail. Over a period of 3 weeks, 18 of each type were mailed from the Network Distribution Center in Atlanta, Georgia, to Des Moines, Iowa. The total delivery time in days was recorded. Minitab was used to perform the ANOVA. The results follow: Source DF SS MS F P Factor 3 1.65 0.55 1.57 0.205 Error 68 24.09 0.35 Total 71 25.74 Level N Mean...
Your mail-order company advertises that it ships 90% of its orders within three working days. You...
Your mail-order company advertises that it ships 90% of its orders within three working days. You select an SRS of 100 of the 5000 orders recieved in the past week for an audit. The audit reveals that 86 of these orders were shipped on time. (a) If the company really ships 90% of its orders on time, what is the probability that 86 or fewer in an SRS of 100 orders are shipped on time? (b) A critic says "Aha!...
Your mail-order company advertises that it ships 90% of its orders within three working days. You...
Your mail-order company advertises that it ships 90% of its orders within three working days. You select an SRS of 100 of the 5000 orders recieved in the past week for an audit. The audit reveals that 86 of these orders were shipped on time. (a) If the company really ships 90% of its orders on time, what is the probability that 86 or fewer in an SRS of 100 orders are shipped on time? (b) A critic says "Aha!...
Your mail-order company advertises that it ships 90% of its orders within three working days. You...
Your mail-order company advertises that it ships 90% of its orders within three working days. You select an SRS of 100 of the 5000 orders received in the past week for an audit. The audit reveals that 86 of these orders were shipped on time. Note: It could be assumed that it satisfies all four conditions of the Binomial experiment. a) If the company really ships 90% of its orders on time, what is the probability that 86 or fewer...
ADVERTISEMENT
Need Online Homework Help?

Get Answers For Free
Most questions answered within 1 hours.

Ask a Question
ADVERTISEMENT