To receive Grade ‘A’ in a course, one must obtain an average of 90 marks or more in five examinations (each of 100 marks). If Sunita's marks in first four examinations are 87, 92, 94 and 95, find minimum marks that Sunita must obtain m fifth examination to get grade ‘A’ in the course.

Explanation

Let minimum marks needed by Sunita to get Grade A = x

Then,

`(87+92+94+95+x)/5 = 90`

`=>368+x = 450`

`=>x=82`