Add days to date in Go

I’m trying to add a number of days (actually a number of weeks) to an existing date in Go. I have tried myDate.Add(time.Hour * 24 * 7 * weeksToAdd)

But I get an error when I try to build: invalid operation: time.Hour * startAdd (mismatched types time.Duration and float64)

So weeksToAdd is currently a float64 , but I can change it to an int or whatever. Changing it to an int only changed my error to say that int and Duration can’t be multiplied.

How do I add days to a date?