The shortcut on this calculator
The shortcut: type 400, press 
, type 30, then 
and 
. The calculator works out 30% of 400 by itself and takes it off: 280., in one step.
The shortcut: type 400, press , type 30, then and . The calculator works out 30% of 400 by itself and takes it off: 280., in one step.
▶ Watch this step in the video (27:09)