If X+Y = 2X+2Z, X-2Y = 2Z and X+Y+Z = 21, what is the value of Y/Z?  Answers.
A) -4. B) -2. C) -1.7. D) 3. E) 2.5.
X+Y = 2X+2Z   Y= X+2Z---------- 1   X-2Y = 2Z   X-2Z= 2Y--------- 2   Subtracting equation 1 from equation 2   -4Z= Y   Y/Z= -4   -4. is the answer
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If X+Y = 2X+2Z, X-2Y = 2Z and X+Y+Z = 21, what is the value of Y/Z?