General calculators don't have this function, so they need more complicated scientific calculators with "ab/C" key.
The first press is between numerator and denominator, and the second press is between integer and fraction.
For example, press 2 first and then 5, and the result is 2/5 = 0.5; Press 2 first, then 5, then 7, and the result is 2 5/7=2.7 14…
To press "5 plus 5/6 divided by 2 plus 12 plus 1", you need to press "ab/C", then "5", then "6", then \ \, then "ab/C" and then "2".
Extended data:
Application mode
Calculator includes standard type and scientific type, in which the usage of standard type is as follows:
1. When typing a number, press the corresponding number key. If you press the wrong number, you can use the (CE) key to delete a number, and then re-enter the correct number.
2. After directly inputting the number, press the multiplication symbol to become a multiplier, and directly press the (=) key to calculate the formula diagram, without inputting the multiplicand, which is the quadratic value of the number.
3. The root sign (√) key opens the square root twice by default, and only scientific calculators can open the square root multiple times.
4. Press the (+/-) key to change the positive and negative values of numbers.
Reference: Baidu Encyclopedia-Calculator