static float floatAverage(int... a) {
  float sum = 0;
  for i over a:
    sum += a[i];
  ret floatRatio(sum, l(a));
}

static float floatAverage(float... l) {
  ret floatRatio(floatSum(l), l(l));
}

static float floatAverage(Collection<Float> l) {
  ret floatRatio(floatSum(l), l(l));
}