swift - Calculate average pace -

i need convert decimal hour in hh:mm:ss display average pace walking app.

i have converted time decimal , have calculated pace in decimal unsure how convert time.

my timedecimal is:

let timedecimal:double = (hoursource + (minutesource / 60) + (secondsource / 3600)) / distancesource 

which gives me 0.4375

0 = 0 .4375 * 60 = 26.25 .25 = * 60 = 15 

i know time should 00:26:15 not sure formula achieve without splitting result , performing multiplication multiple times.

any appreciated.

let formatter = nsdatecomponentsformatter() formatter.allowedunits = [ .hour, .minute, .second ] formatter.unitsstyle = .positional formatter.zeroformattingbehavior = .pad let string = formatter.stringfromtimeinterval(0.4375 * 3600)! 

result: 0:26:15.