Terminology

 Benchmark (e.g., “round” numbers like multiples of 10)

 Endpoint (point where something begins or ends) 

     Estimate (an approximation of a quantity or number) 

     Hash mark (marks on a ruler or other measurement tool)

 Meter (standard unit of length in the metric system)

 Meter stick or strip (tool used to measure length)

 Number line 

 Overlap (extend over, or cover partly)

 Ruler (tool used to measure length)