The amount of time that Kelly uses her phone at work on any given day is uniformly distributed between 48 and 85 minutes. Ass that the amount of time that Kelly uses her phone at work is independent from day to day. Find the probability that Kelly used her phone for more than 61 minutes on Monday or between 53 and 76 minutes on Wednesda Answer:

Marlene has noticed that she spends a lot of time in front of a screen. She spends all day working in front of a computer screen, she spends time relaxing and watching her favourite shows in front of a TV screen and before she goes to sleep she spends time looking at things on her phone screen. Marlene thinks she should probably cut down on the time she spends on her phone before going to sleep. On any given night, Marlene believes that the amount of time she spends on her phone is uniformly distributed between 41.3 and 73.4 minutes. Assume that the amount of time Marlene spends on her phone is independent from night to night.

The number of phone calls per five minutes in an office has a mean of six.(a) What is the probability there will be exactly five calls in a five-minute period?

Assume the length X, in minutes, of a particular type of telephoneconversation is a random variable with probability density function( )/51 , 0,50,xe xf xotherwise− = a. Determine the mean length X of this type of telephoneconversation.b. Find the variance and standard deviation of X.c. Find( )25X  + 

Question 7A statistical analysis of 2,000 long-distance telephone calls made from the headquarters of theBricks and Clicks Computer Corporation indicates that the length of these calls is normallydistributed, with 𝜇 = 300 seconds and 𝜎 = 50 seconds. (4 marks)(a) What is the probability that a call lasted less than 210 seconds?(b) What is the probability that a call lasted between 210 and 320 seconds?(c) What is the probability that a call lasted between 100 and 210 seconds?(d) 10% of all calls will last less than how many seconds?

A Customer Telephone Center receives 1,200 calls in a 24-hour period. Of these calls, 75% occur between 9:30 a.m. and 3:30 p.m., and calls are evenly distributed during this time. If each person handles 10 calls an hour, how many people are needed to handle calls during these hours?2018515