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In a cinema hall, there are three entrance doors and two exit doors. In how many ways can a person enter the hall and then come out?
By BYJU'S Exam Prep
Updated on: September 25th, 2023
(A) 6
(B) 4
(C) 9
(D) None of these
In a cinema hall, there are three entrance doors and two exit doors. In 6 ways, a person can enter the hall and then come out.
Fundamental Principle of Multiplication: Let’s say A and B are the two tasks, with A having m distinct methods to complete it and B having n different ways to complete it. Then, the M N method gives the total number of ways to finish tasks A and B sequentially.
Fundamental Principle of Addition: Let’s assume that A and B are the two projects, each of which can be completed in m distinct ways and in n different ways, respectively. Then, (m + n) ways are the number of ways to finish each of the two assignments.
Calculation:
Given: A movie theatre has 2 exit doors and one entrance door.
Therefore, there are 3 possible entrances to the hallway.
Similar to that, there are two routes to leave the hallway.
As we are aware, if the tasks A and B may each be completed in m different ways, then task B can also be completed in n different ways. The number of ways to execute tasks A and B sequentially is written as: m n methods.
As a result, there are 6 possible ways to enter the hallway and exit it.
Consequently, there are six different ways to enter the hall.
Summary:
In a cinema hall, there are three entrance doors and two exit doors. In how many ways can a person enter the hall and then come out? (A) 6 (B) 4 (C) 9 (D) None of these.
There are three entrance doors and two exit doors in a movie theatre. There are six different methods to enter the room and exit it. Such questions are usually asked in competitive exams to test the knowledge of students.
