# Questions about 4 answer choices

**URL:** <https://forum.code.org/t/questions-about-4-answer-choices/9849>\
**Category:** Unit and Lesson Discussion\
**Tags:** csp-unit-1\
**Created:** [August 31, 2017, 2:39am UTC](https://forum.code.org/t/questions-about-4-answer-choices/9849 "2017-08-31T02:39:33Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![kathryn\_cogdell](https://avatars.discourse-cdn.com/v4/letter/k/8491ac/32.png) [@kathryn\_cogdell](https://forum.code.org/u/kathryn_cogdell)\
**Post date:** [August 31, 2017, 2:39am UTC](https://forum.code.org/t/questions-about-4-answer-choices/9849/1 "2017-08-31T02:39:33Z")

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Can anyone help me with the check your understanding question about a question that has 4 answers? How did you get the answer to be 2 bits

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**Author:** ![bhatnagars](https://sea2.discourse-cdn.com/flex016/user_avatar/forum.code.org/bhatnagars/32/4919_2.png) [@bhatnagars](https://forum.code.org/u/bhatnagars)\
**Post date:** [August 31, 2017, 3:34am UTC](https://forum.code.org/t/questions-about-4-answer-choices/9849/2 "2017-08-31T03:34:26Z")

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Using two symbols 0 and 1 (binary messages) and 2 bits, there are four different permutations possible 00, 01, 10, and 11. Hence the answer is 2 bits. With 1 bit there are only 2 possible answers (0 and 1) and with 3 bits, there are 8 possible answers (000, 001, 010, 011, 100, 101, 110, 111). I hope this helps!

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**Author:** ![kathryn\_cogdell](https://avatars.discourse-cdn.com/v4/letter/k/8491ac/32.png) [@kathryn\_cogdell](https://forum.code.org/u/kathryn_cogdell)\
**Post date:** [August 31, 2017, 11:58am UTC](https://forum.code.org/t/questions-about-4-answer-choices/9849/3 "2017-08-31T11:58:57Z")

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Fantastic Thanks so much!

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**Author:** ![sraper](https://avatars.discourse-cdn.com/v4/letter/s/a8b319/32.png) [@sraper](https://forum.code.org/u/sraper)\
**Post date:** [August 17, 2018, 3:11am UTC](https://forum.code.org/t/questions-about-4-answer-choices/9849/4 "2018-08-17T03:11:40Z")

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I’m glad this has come up before. This is my first year to teach this. I had the same question about the answer. I thought i was on the right track, but there was no explanation as to why the answer was corrrect. Thanks!