### Combinatorics

Posted:

**Tue Mar 27, 2018 6:10 pm**In how many ways can COMPUTER be spelled by moving either down or diagonally to the right showed in the figure below??

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Posted: **Tue Mar 27, 2018 6:10 pm**

In how many ways can COMPUTER be spelled by moving either down or diagonally to the right showed in the figure below??

Posted: **Fri Oct 19, 2018 1:49 am**

The answer should be 14.

Posted: **Mon Dec 17, 2018 5:47 pm**

HOW??????????????????????

Posted: **Mon Dec 17, 2018 5:49 pm**

HOW??????????????????????

Posted: **Thu Jan 10, 2019 9:45 am**

Count carefully acclrding the question.

Posted: **Mon Jan 14, 2019 6:19 pm**

I still can't understand.

Posted: **Wed Jan 16, 2019 8:42 pm**

If repeated letters distract you, replace these in the following way, because the question basically asks you to choose and count properly:

A

B C

D E F

G H I J

From A, you have 2 choices: AB and AC (one down and the other right-down diagonally).

From each of AB and AC, you have also 2 choices: ABD, ABE and ACE, ACF. Total count up to the third row is, therefore, 4 or (2 × 2)

From each of ABD, ABE, ACE, and ACF, you have also 2 choices.

Can you see a pattern now and complete?

A

B C

D E F

G H I J

From A, you have 2 choices: AB and AC (one down and the other right-down diagonally).

From each of AB and AC, you have also 2 choices: ABD, ABE and ACE, ACF. Total count up to the third row is, therefore, 4 or (2 × 2)

From each of ABD, ABE, ACE, and ACF, you have also 2 choices.

Can you see a pattern now and complete?