bailey's mean score on 5 assessments is 73. what does she need to make on her next 2 assessments for her average to be at least a 78?

This is a weighted average.






Her two scores must add to 181

the average of four numbers is 82. when the fifth number was added the average became 83 what is the fifth number?

(4/5)82+(1/5)x=83 

which leads us to x=91 

:)

My overall grade is an 86% I want to figure out what I need to score on my exam to get an A. My exam is worth 25% of my grade.

Solve this inequality: 
 


to get
x>102 
It is impossible to get an A 

:( 

Suppose your average, after taking 4 quizzes, is 72 (out of 100). What must your average be on the next 5 quizzes to increase your average to 77 out of 100?

This is a weighted average: 

 
so that x=81 


:)

Luke got an 88 on his test. His test grade counts as 15% of his final grade. His current grade is 97. What is his final grade?

This is a weighted average:
grade=(88)(0.15)+(97)(0.85)=95.65 

:)

If I get a 57% on the final exam that is worth twenty percent of my grade and I have a 78 in the class what will my grade be?

your weighted average is:

w=0.57*20+0.78*80=73.8


assuming 70% - 79% is a C

your grade is C

The average of A and B is 6. The average of X,Y, and Z is 16. What is the average of A,B,X,Y, and Z?

This is a weighted average where A, B contributes 2/5 and X,Y, Z contributes 3/5 

Ave=(2/5)(6)+(3/5)(16) = 12 


:)