Due to the high incidence of crime, a company is giving its employees new and secured access to the company. Instead of leaving the doors open, they are installing a card system. To open the door, employees must insert a card into a slot. If a green light comes on, it is okay to turn the handle and open the door; if a yellow light comes on it indicates the door is locked from inside and you cannot enter. Suppose that 90% of the time when the card is inserted, the door should open because it is not locked from the inside. When the door should open, the system makes errors 2% of the time. That is, the green light will appear 98% of the time. When the door should not open, the system makes errors 5% of the time (green light appears). Suppose you inserted the card and the light is green, what is the probability the door will open?

Due to the high incidence of crime, a company is giving its employees new and secured access to the company. Instead of leaving the doors open, they are installing a card system. To open the door, employees must insert a card into a slot. If a green light comes on, it is okay to turn the handle and open the door; if a yellow light comes on it indicates the door is locked from inside and you cannot enter. Suppose that 90% of the time when the card is inserted, the door should open because it is not locked from the inside. When the door should open, the system makes errors 2% of the time. That is, the green light will appear 98% of the time. When the door should not open, the system makes errors 5% of the time (green light appears). Suppose you inserted the card and the light is green, what is the probability the door will open?

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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