Answer:
Equivalent ratio states that the two ratios express the same relationship between the numbers.
As per the given statement:
There are 12 snowflakes and 18 snowmen.
⇒ Number of snowflakes = 12 and
Number of snowmen = 18
By definition of equivalent ratio:

divide both numerator and denominator by 6 we get;
⇒

or we can write this as:
3 : 2
Therefore, the equivalent ratio of snowmen and snowflakes in simplest form using a colon is; 3 : 2