A ratio of 2 to 1 simply means that for every 2 of something, there is 1 of something else, with a total of 3.
EXAMPLE:
The directions called for 2 to 1 water, chemical. Meaning 2 parts water to 1 part chemical.
2 TO 1 or 2:1
A ratio of 2 to 1 simply means that for every 2 of something, there is 1 of something else, with a total of 3.
EXAMPLE:
The directions called for 2 to 1 water, chemical. Meaning 2 parts water to 1 part chemical.