The sum of the series \[6+66+666+..........\]upto \[n\] terms is [IIT 1974]

The sum of the series \[6+66+666+..........\]upto \[n\] terms is [IIT

1.	The sum of the series \[6+66+666+..........\]upto \[n\] terms is [IIT 1974]
A.	\[({{10}^{n-1}}-9n+10)/81\]
B.	\[2({{10}^{n+1}}-9n-10)/27\]
C.	\[2({{10}^{n}}-9n-10)/27\]
D.	None of these
Answer» C. \[2({{10}^{n}}-9n-10)/27\]

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The sum of the series \[6+66+666+..........\]upto \[n\] terms is [IIT 1974]

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