WBJEE · Maths · Permutation Combination
From a collection of 20 consecutive natural numbers, four are selected such that they are not consecutive. The number of such selections is
- A \(284 \times 17\)
- B \(285 \times 17\)
- C \(284 \times 16\)
- D \(285 \times 16\)
Answer & Solution
Correct Answer
(A) \(284 \times 17\)
Step-by-step Solution
Detailed explanation
Given, numbers are \(1,2,3 \ldots \ldots .20\) Here, number of ways of selecting four consecutive numbers \(=17\) \(\because\) Required number of selecting 4 non-consecutive…
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