How can I create a strong password to protect my online accounts?

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Discussion Overview

The discussion revolves around solving combinatorial problems related to arranging books and calculating combinations for a lock. It includes specific homework questions that require explanations and reasoning in combinatorial mathematics.

Discussion Character

  • Homework-related
  • Mathematical reasoning

Main Points Raised

  • One participant asks for help with three combinatorial problems involving arrangements of books and combinations for a lock.
  • Another participant provides hints for the first problem, suggesting to treat books of the same language as a single object and to use the fundamental counting principle.
  • Hints are also given for the second problem regarding the arrangement of vowels in the word "equation," treating vowels as a single letter.
  • For the third problem, the participant explains how to calculate combinations with and without repetition of digits.
  • A later reply mentions that the initial participant had already completed their homework by the time they received the hints.

Areas of Agreement / Disagreement

Participants generally agree on the approach to solving the problems, with one participant emphasizing the importance of learning rather than simply receiving answers. However, there is no explicit consensus on the final answers to the problems posed.

Contextual Notes

The discussion does not resolve the specific numerical answers to the combinatorial problems, and the assumptions underlying the hints provided are not fully explored.

Asawira Emaan
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Asalamoalikum,

Kindly can someone solve these with explanation?

1. In how many ways can four French books, two English books and three German books be arranged on a shelf so that all books in same language are together.

2. How many different arrangements can be formed of the word "equation" if all the vowels are to be kept together?

3. A combination lock has five wheels, each labeled with the ten digits from 0 to 9. How many five number opening combinations are possible,
(i) assuming no digit is repeated.
(ii)assuming digits can be repeated.

Thank you.
 
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Asawira Emaan said:
Asalamoalikum,

Kindly can someone solve these with explanation?
You won't learn anything by people doing your homework for you! Here are some hints:

1. In how many ways can four French books, two English books and three German books be arranged on a shelf so that all books in same language are together.
First, treat the books of each language, which must be kept together, as one object. In how many ways can you arrange 3 objects? Now, in how many ways can you arrange just the 4 French books? The two English books? The three German books? By the "fundamental counting principle", multiply those.

2. How many different arrangements can be formed of the word "equation" if all the vowels are to be kept together?
Treat the vowels, e, u a, i, and o, that are to be kept together, as a single letter. there are also 3 consonants so, treating the vowels as a single letter, there are 4 objects. In how many ways can you arrange 4 objects. In how many ways can you arrange the 5 vowels?

3. A combination lock has five wheels, each labeled with the ten digits from 0 to 9. How many five number opening combinations are possible,
(i) assuming no digit is repeated.
There are 10 choices for the first digit, then 9 for the second, etc.

(ii)assuming digits can be repeated.
Then there are 10 choices for every digit.

Thank you.
 
Country Boy said:
You won't learn anything by people doing your homework for you! Here are some hints:First, treat the books of each language, which must be kept together, as one object. In how many ways can you arrange 3 objects? Now, in how many ways can you arrange just the 4 French books? The two English books? The three German books? By the "fundamental counting principle", multiply those. Treat the vowels, e, u a, i, and o, that are to be kept together, as a single letter. there are also 3 consonants so, treating the vowels as a single letter, there are 4 objects. In how many ways can you arrange 4 objects. In how many ways can you arrange the 5 vowels?There are 10 choices for the first digit, then 9 for the second, etc.Then there are 10 choices for every digit.
Thanks by the time I got this answer I had already done the homework.
 
Good! That's the way it should be!
 

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