4-letter Code Words

For students of class 9-10 (age 14-16)
User avatar
Tasnood
Posts: 73
Joined: Tue Jan 06, 2015 1:46 pm

4-letter Code Words

Unread post by Tasnood » Mon Jan 21, 2019 12:14 am

How many $4$-letter code words can be formed from the letters in $CALCULUS$?

User avatar
samiul_samin
Posts: 1004
Joined: Sat Dec 09, 2017 1:32 pm

Re: 4-letter Code Words

Unread post by samiul_samin » Mon Jan 21, 2019 11:04 am

Tasnood wrote:
Mon Jan 21, 2019 12:14 am
How many $4$-letter code words can be formed from the letters in $CALCULUS$?
What means code words?

User avatar
Tasnood
Posts: 73
Joined: Tue Jan 06, 2015 1:46 pm

Re: 4-letter Code Words

Unread post by Tasnood » Mon Jan 21, 2019 8:58 pm

Doesn't need to have a meaning of the new words

User avatar
samiul_samin
Posts: 1004
Joined: Sat Dec 09, 2017 1:32 pm

Re: 4-letter Code Words

Unread post by samiul_samin » Mon Jan 21, 2019 10:46 pm

Tasnood wrote:
Mon Jan 21, 2019 8:58 pm
Doesn't need to have a meaning of the new words
Answer
$354$
Solution
Total $8$ letters.

There are three cases:
Case $1$:
All different letters
$120$

Case $2$:
$2$ differnt and $2$ same letters
$216$

Case $3$:
$2$ same and other $2$ same
$18$

Answer=$120+216+18=354$

Post Reply