rebol [
  title: "compute average"
  author: "vpavlu"
  date: 9-Dec-2002/12:57
  home: http://plain.at/vpavlu
]

block: [23 7 0 -14 3.14159 2 16]

sum: 0
foreach num block [
  sum: sum + num
]

print [ "average is" (sum / length? block) ]