Mr taylor has 18 students in his class and 3 of them are left handed. what is the ratio of right handed students to left handed students?

To determine the number of right handed students, subtract the number of left handed students from the total number. 
 
                                            right handed = total - left handed

Substituting the given, 
 
                                             right hand = 18 - 3 = 15

Calculate for the ratio of the right handed to left handed through dividing 15 by 3 which will be further simplified. 
      
                                                 15/ 3 = 5/ 1

Therefore, the ratio of the right handed to left handed students is 5:1