convert positive number to negative

[Anonymous]

Am looking to convert a positive number to negative based on another column. For example

Numbers of users = 29 and converted monthly price = -100 then i would need the number of users 29 to be converted to -29 below is an outline of the data i am looking at. So for every negative value in ConvertedMonthlyPrice needs to convert the numberofusers value from a positive to a negative. Any help would be amazing 

[tex628 · Accepted solution]

Column =
IF(ConvertedMonthlyPrice] < 0 ,
[NumberOfUsers] * -1 ,
[NumberOfUsers]
)