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1 vote
Mrs. Wei was designing a 6 question True or False quiz. She did

not want there to be more than 2 answers the same in a row.
How many ways could the answer key be designed to fit the
criteria?



User Gkatiforis
by
8.3k points

1 Answer

4 votes

The answer key be designed to fit the criteria is 12 ways for Mrs.Wei

Solution:

Given, Mrs. Wei was designing a 6 question True or False quiz.

She did not want there to be more than 2 answers the same in a row.

We have to find how many ways could the answer key be designed to fit the criteria?

Given that, more than 2 continuous answers are not allowed.

So, one answer same in a row conditions are t f t f t f or f t f t f t ⇒ 2 ways.

And, two answers same in a row conditions are

Condition 1:

t t f f t t t t f t f t t t f t t f

⇒3 ways by keeping 1st two answers same and constant and total 6 ways by interchanging true with false.

Condition 2:

f t t f f t f t t f t f

⇒ 2 ways by keeping 2nd two answers same and constant and total 4 ways by interchanging true with false.

Condition 3:

Next, f f t t f f ⇒ this is covered in 1st case when we interchange true with false.so, we are done with possibilities.

So, total ways are 2 + 6 + 4 = 12 ways.

Hence, there are 12 ways.

User Thuy Trinh
by
8.8k points
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