+0  
 
0
157
8
avatar+11847 

can anyone pls answer the first one!!!??

 

https://web2.0calc.com/questions/permutations-and-combinations-lt-3

rosala  Feb 10, 2018
edited by rosala  Feb 10, 2018
Sort: 

8+0 Answers

 #1
avatar+6943 
+2

Hey rosala, your link doesn't need the  " /new "  at the end...it should just be

 

https://web2.0calc.com/questions/permutations-and-combinations-lt-3

 

smiley

hectictar  Feb 10, 2018
 #2
avatar+11847 
+1

thanks hectictar for noticing..i appreciate it!thank you! smiley

rosala  Feb 10, 2018
 #3
avatar+12227 
0

error   error  I saw an answer for this, but it has been deleted....maybe because it was incorrect,,,   sorry

ElectricPavlov  Feb 10, 2018
edited by Guest  Feb 10, 2018
edited by Guest  Feb 10, 2018
 #5
avatar
0

No, this one wasn't.

Guest Feb 10, 2018
 #4
avatar
0

1.Find the no. of permutations of letters a , b , c , d, e , f , g taken all at a time if neither  “beg” nor “cad” patterns appear in any word.

 

Permuatations of 7 letters =7! =5,040

The word "beg" appears in 7 - 3 + 1 = 5 positions

The remaining 4 letters permute in 4! =24 ways

5 x 24 = 120 pemutations

 

Similarly, the word"cad" appears in 7 -3 + 1=5 positions

The remaining 4 letters permute in 4! = 24 ways

5 x 24 = 120 permutations.

 

The combinations of the word "beg" and "cad" as one word "begcad" appears in 7 - 6 + 1 =2 positions only. Similarly, the word "cadbeg" also appears in 2 positions only for a total of 4 words. Each one of these words is excluded twice, once when it is included in the 120 permuations of "beg" and once in the permutations of the word "cad". So these 4 words should be added back to the total.

 

So, the total permuations left should be  =5,040 -120 - 120 + 4 =4,804 permutations.

Melody: You are pretty good at this kind of problem, so, please take a look at it.

Guest Feb 10, 2018
 #6
avatar
0

What about this permunation?:

 

B-E-G-F-C-A-D

Guest Feb 11, 2018
 #8
avatar+92174 
0

Certainly I can do that :))

NOTE: I have not looked at your answer. 

I have answered on Rosala's original thread as indicated below :)

Melody  Feb 11, 2018
 #7
avatar+92174 
0

Hi Rosala,

I have anwered on the original thread :)

 

https://web2.0calc.com/questions/permutations-and-combinations-lt-3#r9

Melody  Feb 11, 2018

8 Online Users

avatar
We use cookies to personalise content and ads, to provide social media features and to analyse our traffic. We also share information about your use of our site with our social media, advertising and analytics partners.  See details