# Common Difference

Pronunciation: /ˈkɒm.ən ˈdɪ.frəns/ Explain

The common difference in an arithmetic sequence is the constant difference between any term and the term after it.[2][3][4]

For example, the arithmetic sequence { 1, 3, 5, 7, 9 } has a common difference of 2. You can see that 3 - 1 = 2, and 5 - 3 = 2. Check the rest of the terms. Each term is 2 more than the term before it.

### Understanding check

1. What is the common difference of { 4, 7, 10, 13 }? Click here for answer
2. What is the common difference of { -1, 1, 3, 5 }? Click here for answer
3. What is the common difference of { 4, 6, 9, 13 }? Click here for answer
4. What is the next number in the sequence { 1, 5, 9, ? }? Click here for answer
5. What is the next number in the sequence { 2, 4, 6, ? }? Click here for answer

### References

1. McAdams, David E.. All Math Words Dictionary, common difference. 2nd Classroom edition 20150108-4799968. pg 37. Life is a Story Problem LLC. January 8, 2015. Buy the book
2. common difference. merriam-webster.com. Encyclopedia Britannica. Merriam-Webster. Last Accessed 6/25/2018. http://www.merriam-webster.com/dictionary/common difference. Buy the book
3. Bettinger, Alvin K. and Englund, John A.. Algebra and Trigonometry. pp 260-262. www.archive.org. International Textbook Company. January 1963. Last Accessed 6/25/2018. http://www.archive.org/stream/algebraandtrigon033520mbp#page/n277/mode/1up/search/progression. Buy the book
4. Rivenburg, Romeyn Henry. A Review of Algebra. pg 47. www.archive.org. American Book Company. 1914. Last Accessed 6/25/2018. http://www.archive.org/stream/reviewofalgebra00riverich#page/47/mode/1up/search/progression. Buy the book

McAdams, David E. Common Difference. 4/13/2019. All Math Words Encyclopedia. Life is a Story Problem LLC. https://www.allmathwords.org/en/c/commondifference.html.

### Revision History

12/21/2018: Reviewed and corrected IPA pronunication. (McAdams, David E.)