The real numbers x,y and z satisfy the equations x+2y+3z=950 and 3x+2y =1450 and y + 3z = 500. What is the average of x, y and z?
+9 Guest
x + 2y + 3z = 950 (1)
3x + 2y + 0 = 1450 (2)
0 + y + 3z = 500 (3)
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Step 1: Add (2) + (3).
3x + 3y + 3z = 1950
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Step 2: Divide the equation by 3.
x + y + z = 650
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Step 3: Calculate the average.
x + y + z 650
-------------- = ------
3 3
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Step 4: Final
The average of x, y and z are 650/3, approximately 216,67.
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