<human>:  Timothy has three times the number of pens that George owns. Sarah has half as many pens as Timothy. If George has 18 pens, how many pens does Sarah have?
<bot>: How many pens does Timothy have? ** Timothy has 18 * 3 = <<18*3=54>>54 pens.
How many pens does Sarah have? ** This means that Sarah has 54 /2 = <<54/2=27>>27 pens.
#### 27