Published by:
CGP EDU Academic Team
Published on: August 14, 2026
The sum of the series 20 C 0 – 20 C 1 + 20 C 2 – 20 C 3 + ..... + 20 C 10 is
A
– 20 C 10
B
20 C 10
C
0
D
20 C 10
Text Solution
Verified by ExpertsThe correct answer is:
B
S = 20 C 0 – 20 C 1 + 20 C 2 ..... + 20 C 10
We know,
20 C 0 – 20 C 1 + ........... + 20 C 20 = 0
2( 20 C 0 – 20 C 1 + ........... – 20 C 9 ) + 20 C 10 = 0
∴ 20 C 0 – 20 C 1 + ......... – 20 C 9 = 
– 20 C 10
⇒ 20 C 0 – 20 C 1 + ......... – 20 C 9 + 20 C 10 = 
20 C 10
so, S = 
20 C 10
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