Question

John's grades in Algebra are: 65, 83, and 93. What grade does John need on the final exam to get an 85
average (mean)?

Answer 1

Answer:

99 marks

Step-by-step explanation:

Let 'x' be the mark in final exam

Sum of all the data's/ Number of data's = Mean

$\frac{65+83+93+x}{4}=85\\\\\\\frac{241+x}{4} = 85$

241 + x  = 85*4

241 + x = 340

       x = 340 - 241

x = 99