This is a famous calculator riddle in which you must display 100 on the display screen considering below three rules must be followed.A) Three unique keys are allowed to be pressed.B) You cannot press Memory keys C) Only basic calculator can be used.

100 Display Calculator Riddle

Solution (A)
Press 1
Press 0
Press 0
Press =
Note: Three unique keys are "1", "0" and "="

Solution (B)
Press 1
Press / (divide)
Press % (percent)
Press / (divide) .... this step may not require in all calculator.
Note: Three unique keys are "1", "/" and "%".

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