Answer:
Ratio as a fraction in simplest form is,
Step-by-step explanation:
Ratio defined as the relationship between the quantities of something i.e,
a: b = 
Given: 51 correct : 9 incorrect
By definition of ratio:
51 correct : 9 incorrect = 
Divide both numerator and denominator by 3 we get;

then
The ratio as a fraction in simplest form is, 17 correct : 3 incorrect or 