question: Mary has 30 sheep. She gets 1 kg of milk from half of them and 2 kg of milk from the other half every day. How much milk does she collect every day?
answer: Half of the sheep is 30 / 2 = <<30/2=15>>15.
  Mary gets (15 * 1) + (15 * 2) = <<15*1+15*2=45>>45 kg of milk every day.
  #### 45