Skillington is a village and civil parish in the South Kesteven district of Lincolnshire, England. The population of the civil parish at the 2011 census was 345. It is situated 1.5 mi west from the A1 road, 6 mi south from Grantham, and is within 3 mi of the Leicestershire border.
The population of Skillington in 2012 was 350.
It's neither correct nor incorrect because we don't know what the population in 2012 was. It's difficult for the system because the text mentions the population 2011, so it probably assumes the statement must be either incorrect/correct based on the information provided.