Question

Problem 1. Sam has Average of three marking periods M3 = 89. What grade he

need in MP4 to get Final Average: Mf = 91

Answer 1

First, let’s make an equation

(M1 + M2 + M3 + M4)/4 = 91


Now let’s just assume that M1-3 all equal 89

(89 + 89 + 89 + M4)/4 = 91

(267 + M4)/4 = 91

Now let’s apply the multiply both sides by 4


267 + M4 = 364


And subtract 267 from both sides


M4 = 97


To check plug into the original equation:


(89 + 89 + 89 + 97)/4 = 91





Final answer: Sam needs a 97 in M4