Random yoyo()

i have this for my yoyoing an it works fine:

[FONT=Courier New]
var mouth:Tween = [COLOR=#000000]new[/COLOR] Tween[COLOR=#000000]([/COLOR]m_mc, [COLOR=#ff0000]"_yscale"[/COLOR], Regular.[COLOR=#000080]easeInOut[/COLOR], [COLOR=#000080]100[/COLOR], [COLOR=#000080]110[/COLOR], [COLOR=#000080]4[/COLOR], [COLOR=#000000]false[/COLOR][COLOR=#000000])[/COLOR];
[LEFT]
mouth.[COLOR=#000080]onMotionFinished[/COLOR] = [COLOR=#000000]function[/COLOR]COLOR=#000000[/COLOR]
[COLOR=#000000]{[/COLOR]
[COLOR=#0000ff]this[/COLOR].[COLOR=#000080]yoyo[/COLOR]COLOR=#000000[/COLOR];
[COLOR=#000000]}[/COLOR];

[/LEFT]

[/FONT]

how can i make it yoyo from 100 to say a range between 105 and 115?

so it might go:
100
106
100
110
100
108
100
111
100
114
100
113
100
114