SOLUTION: The average of 4 numbers is 85. If three of the numbers are 76,78, and 81. What is the fourth number

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Question 937077: The average of 4 numbers is 85. If three of the numbers are 76,78, and 81. What is the fourth number

Found 2 solutions by TimothyLamb, Danielshinmath:
Answer by TimothyLamb(4379) About Me  (Show Source):
You can put this solution on YOUR website!
x = 4th number
y = sum of first three numbers
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y = 76 + 78 + 81
y = 235
x = 85*4 - 235
x = 105
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Answer by Danielshinmath(31) About Me  (Show Source):
You can put this solution on YOUR website!
The sum of the 4 numbers is 85*4= 340. To get the other number, you do 340-(76+78+81) to get 340-235=105
ANSWER:340-235=105