SOLUTION: The​ average, or​ mean, D​, of three exam​ grades, w​, r​, and v​, is given by the following formula. D = w+r+v over 3 ​(a) Solv

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Question 1119359: The​ average, or​ mean, D​, of three exam​ grades, w​, r​, and v​, is given by the following formula.
D = w+r+v over 3
​(a) Solve the formula for v.
​(b) Use the formula in part​ (a) to solve this problem. On your first two​ exams, your grades are 86​% and 89​%: w=86 and r=89. What must you get on the third exam to have an average of 86​%?

Answer by Boreal(15235)   (Show Source): You can put this solution on YOUR website!
D=(w+r+v)/3; 3D=w+r+v; v=3D-w-r
Substitute
v=258-86-89
v=83%

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