M- The number displayed on the screen is counted as a negative value in the memory (adding up to the original memory value is equivalent to subtracting the value from the memory).
MR displays the memory value (if there are multiple memory values, the accumulated value is displayed).
MC Clear Memory Value \ Replace Value (depending on the calculator function, sometimes it is clear memory and sometimes it is replace memory. It is recommended to clear the values displayed on the screen before use, which is equivalent to clearing only the function).
Example 1, 2 * 9 M+ 6/3 M+ MR (that is, the result is displayed)
Example 2, 7 * 8 M+ 9/3 M- MR (i.e. display results)
Note: If the calculator displays M before operation, you must press MC to clear the stored data to get the correct result. In general, it is best to press MC after the operation to clear the data stored in the memory.
M+: Memory addition can add up the values or operation results on the screen and memorize them independently.
M-: Memory subtraction can subtract the numerical values or operation results on the screen and memorize them independently.
MR: total value of outgoing memory
MC: clear stored values
Some calculators have MRC keys: the combination of MR and MC. Click once for MR function, and click twice for MC function.