If \( n = {^mC_2} \) then what is \( {^nC_2} \) equal to ?
- A. ^{m+1}C_4
- B. 2 \times {^{m+1}C_4}
- C. 3 \times {^{m+1}C_4} ✓
- D. ^{m+2}C_4
Correct Answer: C. 3 \times {^{m+1}C_4}
Explanation
Substitute n = m(m-1)/2 into nC2 and simplify. The result factors perfectly into 3 times (m+1)C4.
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