JEE Mains · Maths · STD 11 - 6. permutation and combination
Number of integral solutions to the equation \(x+y+z=21\), where \(x \geq 1, y \geq 3, z \geq 4\), is equal to \(..........\).
- A \(104\)
- B \(105\)
- C \(103\)
- D \(102\)
Answer & Solution
Correct Answer
(B) \(105\)
Step-by-step Solution
Detailed explanation
\({ }^{15} C _2=\frac{15 \times 14}{2}=105\)
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