Understanding 'Good Words'

The video tutorial defines 'good words' as sequences of letters A, B, and C, with specific constraints: A cannot be followed by B, B cannot be followed by C, and C cannot be followed by A. The tutorial explains these constraints and calculates the number of possible seven-letter 'good words' by considering the possibilities for each letter position. The total number of such words is determined to be 192.

What defines a 'good word' in the context of this lesson?

• A sequence of any letters

• A sequence of letters A, B, and C with specific rules

• A sequence of letters A, B, and C without any rules

• A sequence of letters A, B, C, and D

Which letter cannot immediately follow A in a 'good word'?

• A

• B

• None of the above

• C

If a 'good word' starts with B, which letter can follow it?

• Only A

• Only C

• A or B

• B or C

What is the rule for a letter C in a 'good word'?

• C can be followed by any letter

• C can be followed by A or B

• C can be followed by B or C

• C can be followed by A or C

How many possibilities are there for the first letter in a 'good word'?

• 4

• 1

• 2

• 3

For the second letter in a 'good word', how many options are available regardless of the first letter?

• 2

• 3

• 4

• 1

What is the total number of possibilities for a seven-letter 'good word'?

• 64

• 128

• 192

• 256

How is the total number of 'good words' calculated?

• 3 times 2 to the fifth power

• 3 times 2 to the sixth power

• 3 times 2 to the seventh power

• 3 times 2 to the eighth power

What is the significance of the number 192 in this lesson?

• It is the number of constraints

• It is the number of letters used

• It is the number of possible 'good words'

• It is the number of rules

Which of the following sequences is a 'good word'?

• ABCABC

• CACACA

• BCBCBC

• ABACAB