Appending numbers to variable name

1

for(i=0; i<16; i++){

var ball+i: ball_mc = new ball_mc();

addChild(ball+i);

ball+i.x = 100;
ball+i.y = 100;
ball+i.scaleX = 0.5;
ball+i.scaleY = 0.5;

}

i basically want to create multiple instances