The percentage resistance and percentage reactance of a 10 kVA, 400 V / 200 V, 3-phase transformer are 2% and 10% respectively. If the constant losses in the machine are 1%, the maximum possible percentage efficiency of the transformer is _______ .

The percentage resistance and percentage reactance of a 10 kVA, 400 V

1.	The percentage resistance and percentage reactance of a 10 kVA, 400 V / 200 V, 3-phase transformer are 2% and 10% respectively. If the constant losses in the machine are 1%, the maximum possible percentage efficiency of the transformer is _______ .
A.	97.25
B.	57.25
C.	67.75
D.	None of the above
Answer» B. 57.25

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The percentage resistance and percentage reactance of a 10 kVA, 400 V / 200 V, 3-phase transformer are 2% and 10% respectively. If the constant losses in the machine are 1%, the maximum possible percentage efficiency of the transformer is _______ .

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