CTET Class I to V 17 Jan 2022 Paper

Question : 57 of 150

Marks: +1, -0

Majority of students in a class say$\;{\begin{matrix}\;360\;\\\;\;\text\;"\;"\;\;+\;55\;\\\;\;\end{matrix}}/{}$ is equal 3115.
Revisiting which of the following concepts will be most appropriate to remediate the error?