ios - Swift - generate random Integer between 0.1 and 0.6 -

i'm having trouble swift trying generate random number between 0.1 , 0.6

i want introduce micro delay simple game make iphone having "think" before responding.

i have found various snippets generate random number (none show how decimal numbers).

i've found snippet delay (and if hard code number works)

i trying code start generate random number, divide 10 turn 6 0.6 ..

// delay before playing let lower : uint32 = 1 let upper : uint32 = 6 let delaytime = arc4random_uniform(upper - lower) + lower  delaytime = delaytime / 10 let delay = delaytime * double(nsec_per_sec) let time = dispatch_time(dispatch_time_now, int64(delay))  dispatch_after(time, dispatch_get_main_queue()) {     self.aiturn() } 

xcode tells me line

delaytime = delaytime / 10 

cannot assign 'let' value 'delaytime' - can't divide value of delaytime 10

xcode tells me line

let delay = delaytime * double(nsec_per_sec) 

binary operator * cannot applied operands of type 'uint32' , 'double'

i know i'm mixing int, uint32, int64 , doubles - i've no idea how steer myself out of - appreciated

thanks

okay here working code - @mireke help

// delay before playing     var lower : uint32 = 1     var upper : uint32 = 6     var delaytime = arc4random_uniform(upper - lower) + lower     var delaytimer = double(delaytime) / 10     var delay = delaytimer * double(nsec_per_sec)     var time = dispatch_time(dispatch_time_now, int64(delay))     dispatch_after(time, dispatch_get_main_queue()) {         self.aiturn()     }