The average life of a smart phone of brand A is 7 years and 5 years for brand B, with a known standard deviation of 2 and 3 years respectively. The lives of these smart phones are assumed to follow approximately a normal distribution. Two samples of size 43 and 53 are randomly selected from smart phone of brand A and B. (i) Identify the probability that the mean life of random smart phone A falls between 6.5 and 7.6 years. (ii) Solve the probability mean life of smart phone of brand B is more than 5 years. (iii) Solve the probability that the mean life of a random sample of smart phone brand A is not less than 2.5 years than the sample of smart phone brand B.

The average life of a smart phone of brand A is 7 years and 5 years for brand B, with a known standard deviation of 2 and 3 years respectively. The lives of these smart phones are assumed to follow approximately a normal distribution. Two samples of size 43 and 53 are randomly selected from smart phone of brand A and B. (i) Identify the probability that the mean life of random smart phone A falls between 6.5 and 7.6 years. (ii) Solve the probability mean life of smart phone of brand B is more than 5 years. (iii) Solve the probability that the mean life of a random sample of smart phone brand A is not less than 2.5 years than the sample of smart phone brand B.

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

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