Given: Total number of students (n) =102 Average marks of 102 students (a) =18 Average marks of passed students (x)=26 Average marks of failed students (y)=10 Formula: Number of passed students =n(a−y)/(x−y) Calculations: According to the formula: ⇒n(a−y)/(x−y) ⇒102(18−10)/(26−10) ⇒102×8/16 ⇒51 The number of failed students =102−51 ⇒ 51 ∴ The number of failed students is 51.