Pencils are sold in packs of 12 and erasers in packs of 18. Fatima wants exactly as many pencils as erasers. What is the least total number of packs she must buy?

Explanation

1. 01

   The number of each item must be a common multiple of 12 and 18; least is $\operatorname{LCM} = 36$.

2. 02

   Pencil packs = $36 \div 12 = 3$; eraser packs = $36 \div 18 = 2$.

3. 03

   Total packs = $3 + 2 = 5$.