(a) Based on a recent study, the monthly utility bills for three-room flats in Singapore can be assumed to be normally distributed with mean $135 and standard deviation $42. If a household living in a three-room flat is randomly selected, i. What is the probability that its utility bill is more than $155 ii. What is the probability that its utility bill is between $129 and $165? ii. If 20% of the utility bills for households living in three-room flats are above a certain value V, find the value of V.

(a) Based on a recent study, the monthly utility bills for three-room flats in Singapore can be assumed to be normally distributed with mean $135 and standard deviation $42. If a household living in a three-room flat is randomly selected, i. What is the probability that its utility bill is more than $155 ii. What is the probability that its utility bill is between $129 and $165? ii. If 20% of the utility bills for households living in three-room flats are above a certain value V, find the value of V.

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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