question: Toulouse has twice as many sheep as Charleston. Charleston has 4 times as many sheep as Seattle. How many sheep do Toulouse, Charleston, and Seattle have together if Seattle has 20 sheep?
answer: If Seattle has 20 sheep, Charleston has 4 * 20 sheep = <<20*4=80>>80 sheep
  Toulouse has twice as many sheep as Charleston, which is 2 * 80 sheep = <<2*80=160>>160 sheep
  Together, the three has 20 sheep + 160 sheep + 80 sheep = <<20+160+80=260>>260 sheep
  #### 260