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What grade must I get to have an average of 89%. my grades are 83% and 85%

User Clomez
by
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1 Answer

3 votes

Answer:

  • 99%

==================

Let the required grade be x.

Then the average for three grades is:

  • (83 + 85 + x)/3 = 89

Multiply both sides by 3:

  • 168 + x = 89*3

Subtract 168 from bot sides:

  • 168 + x = 267
  • x = 267 - 168
  • x = 99

You must get a 99%.

User CSharpened
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7.0k points