Constant calculation on the Casio HR100TM calculator refers to a series of entries or operations rather than referring to a designated constant key. Constant calculation works with addition, subtraction, multiplication and division using whole or mixed numbers.
To perform a multiplication constant calculation, enter the constant factor 3.63 and tap the multiplication key twice. The screen displays a "K" on the left, which indicates that the constant lock is activated. Next, enter the other number and tap the equal key. Any number entered after the equal key multiplies by the constant number. For example, 5 * * 1 = 5, 2 = 10 and 3 = 15. Each time you tap the equal key, you can add another number to multiply by 5.