Question
Download Solution PDFIf C(20, n + 2) = C(20, n – 2) then what is n equal to?
Answer (Detailed Solution Below)
Detailed Solution
Download Solution PDFConcept:
The notation C(n, r) is the number of combinations/groups of n different things taking r at a time and is given by:
If C(n, x) = C(n, y), then x + y = n.
Calculation:
Given C(20, n + 2) = C(20, n – 2)
As we know that, if C(n, x) = C(n, y), then x + y = n.
⇒ (n + 2) + (n – 2) = 20
⇒ 2n = 20
⇒ n = 10
Last updated on May 30, 2025
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