Aptitude - Permutation and Combination - Discussion
Discussion Forum : Permutation and Combination - General Questions (Q.No. 12)
12.
How many 4-letter words with or without meaning, can be formed out of the letters of the word, 'LOGARITHMS', if repetition of letters is not allowed?
Answer: Option
Explanation:
'LOGARITHMS' contains 10 different letters.
| Required number of words | = Number of arrangements of 10 letters, taking 4 at a time. |
| = 10P4 | |
| = (10 x 9 x 8 x 7) | |
| = 5040. |
Discussion:
68 comments Page 1 of 7.
PRABHA said:
2 decades ago
I HAVEA DOUDT : 1O C P MEANS 10X9X8X7/(1X2X3X4)
Sahithya said:
1 decade ago
10C4 means 10x 9 x 8 x 7/ (1 x 2 x 3 x 4).
10P4 means 10 x 9 x 8 x 7.
As we are considering order we hav to use permutations.
10P4 means 10 x 9 x 8 x 7.
As we are considering order we hav to use permutations.
(1)
Krishan said:
1 decade ago
I dint get it why we are using permutation here? can you explain.
(1)
Appu said:
1 decade ago
I have one doubt that why permutation is used?.
Here mention that repetation not allowed. Permutation is allowed this that is, ab, ba is allowed.
Can anyone help me.
Here mention that repetation not allowed. Permutation is allowed this that is, ab, ba is allowed.
Can anyone help me.
(1)
Habib said:
1 decade ago
It's said 4 letters , and they dont repeat.!!!!.......
Then how come permutations..which actually implies arrangement of the selected letters at a time...
Pls help me, if i am wrong
Then how come permutations..which actually implies arrangement of the selected letters at a time...
Pls help me, if i am wrong
(1)
Shree Hemalatha said:
1 decade ago
Here why we are using permutation concept and also how we are saying 4 letters s not repeating?
Could me explain me ?
Could me explain me ?
Jagadeesh said:
1 decade ago
How here permutation is used when there is condition letters should not be repeated?
Please explain.
Please explain.
Pritesh said:
1 decade ago
After Selecting the letters in(10 * 9 * 8 * 7) ways those letters can be re-arrange in 4! ways.....
So, according to me answer should be 5040 * 4!
So, according to me answer should be 5040 * 4!
Prawin said:
1 decade ago
It is a four letter word ---- out of 10 repeatition is not allowed so first 10 we have 1 then out of nine wehave 1then out of 8 we have 1 then out of 7 we have 1 so 10*9*8*7=ans
Lydia said:
1 decade ago
It can also be done in another way.
Number of ways of selecting 4 letters from 10 letters=10C4
=(10*9*8*7)/4!
Number of ways of arranging these 4 letters =4P4=4!
So, total number of words formed= [(10*9*8*7)/4!]*4! = 10*9*8*7 = 5040
Am I correct?
Number of ways of selecting 4 letters from 10 letters=10C4
=(10*9*8*7)/4!
Number of ways of arranging these 4 letters =4P4=4!
So, total number of words formed= [(10*9*8*7)/4!]*4! = 10*9*8*7 = 5040
Am I correct?
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