AIR TRAFFIC 1: 60 RULE
It is based on the mathematical principle that a turn of 1 degree at 60 miles is equal to 1 mile displacement at the destination. (right angled triangle where the base is 60 miles. For every degree of angle = 1 mile at the opposite side)
For example: MH1286 is inbound on the ADNUT track heading 090 and is 60 miles away. If you give him a turn of 1 degree left ( heading 089 OR 091 ) then he will be 1 mile RIGHT OR LEFT of track at scHOOL. Likewise, if you give him a turn of 10 degrees left ( heading 080 ) he will be 10 miles left of track. You can also prove this by plotting.
When we (at SATC) talk about speed control sometimes we tend to refer it as 1:60 rule as well. For example a 737 travelling at 300 kts. at 60 NM away. Using 1:60 rule we know that the aircraft will cover about 5NM/min. Therefore, we can estimate the ETA as plus 12 mins. Applying appropriate speed reduction we can fit in the Boeing into our traffic sequence.