Microsoft Excel How to insert formula in Cell

For inserting formula you have to write sign = in a cell where you want to apply formula. After write = sign you should write a letter . Now formula starting with that letter will be appear.

Example1:- Sum formula 
“=sum(C1,C3,C5)”
“=C1+C3+C5”
“=sum(A2:A20)”

 a)Above sum function will add all given 3 cells.
 b)You can write direct by equal sign.
c)Third one will add values from A2 to A20 i.e. in range addition

 Example2:- Substract formulas 
“=sum(C1,-C3,C5)”
“=C1-C3+C5”
“=sum(A2:A20)”

a)Above sum function will add and subtract.
 b)You can write direct by equal sign.
c)Third one will add and subtract values from A2 to A20 i.e. in range addition subtractions negative values will be subtracted.