Think about the situation:
Apoorva and her brother return from school. Their mother serves them some biscuits. While they eat them one by one, Apoorva arranges the biscuits on a  areabiggerbiscuitsborderslengthperimetersurfacetray. She finds that the  areabiggerbiscuitsborderslengthperimetersurfacetray can hold only 12 biscuits. If she has to extend spreading the remaining biscuits also in the same manner, she will need a  areabiggerbiscuitsborderslengthperimetersurfacetray tray in size because, already 12 biscuits occupied the surface of the tray completely.

The total  areabiggerbiscuitsborderslengthperimetersurfacetray of visible  areabiggerbiscuitsborderslengthperimetersurfacetray of the  areabiggerbiscuitsborderslengthperimetersurfacetray is said to be the  areabiggerbiscuitsborderslengthperimetersurfacetray and the  areabiggerbiscuitsborderslengthperimetersurfacetray occupied by the  areabiggerbiscuitsborderslengthperimetersurfacetray is said to be the  areabiggerbiscuitsborderslengthperimetersurfacetray of the tray.