I Need Huge amount of help with building the javascript Calculator app to pass the FCC tests.

I coudn’t figure out how to implement the calculation logic.

Need Help with:

**User Story #12:** I should be able to perform any operation (+, -, *, /) on numbers containing decimal points.

**User Story #13:** If 2 or more operators are entered consecutively, the operation performed should be the last operator entered (excluding the negative (-) sign). For example, if `5 + * 7 =`

is entered, the result should be `35`

(i.e. 5 * 7); if `5 * - 5 =`

is entered, the result should be `-25`

(i.e. 5 x (-5)).

**User Story #15:** My calculator should have several decimal places of precision when it comes to rounding (note that there is no exact standard, but you should be able to handle calculations like `2 / 7`

with reasonable precision to at least 4 decimal places).

Can i get some help ?