8 February 2016

• 21:5321:53, 8 February 2016 diff hist +28 m 2016 AMC 10A Problems/Problem 23 Replaced commas w/ arrows

7 February 2016

• 16:1816:18, 7 February 2016 diff hist +945 2016 AMC 10A Problems/Problem 23 Added third solution; does not involve finding the identity of the operator.

14 August 2014

• 20:3420:34, 14 August 2014 diff hist +10 m Nonnegative number No edit summary
• 20:3420:34, 14 August 2014 diff hist +25 m Positive number added to "see also"