Question:medium
If \( nC_{r-1} = 36 \), \( nC_r = 84 \) and \( nC_{r+1} = 126 \), then the value of \( r \) is:
If \( nC_{r-1} = 36 \), \( nC_r = 84 \) and \( nC_{r+1} = 126 \), then the value of \( r \) is:
Show Hint
Successive binomial coefficients in the middle of a row of Pascal's triangle always show specific ratios. Working with these ratios is much faster than expanding the full factorial definitions.
Updated On: May 1, 2026
- \( 9 \)
- \( 3 \)
- \( 4 \)
- \( 5 \)
- \( 6 \)
Show Solution
The Correct Option is B
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