JEE Mains · Maths · STD 11 - 8. sequence and series
Let the digits \(a, b, c\) be in \(A.P.\) Nine-digit numbers are to be formed using each of these three digits thrice such that three consecutive digits are in \(A.P.\) at least once. How many such numbers can be formed?
- A \(1261\)
- B \(1262\)
- C \(1263\)
- D \(1260\)
Answer & Solution
Correct Answer
(D) \(1260\)
Step-by-step Solution
Detailed explanation
\(\frac{{ }^7 C _1 \times 2 \times 6 !}{2 ! 2 ! 2 !}=1260\)
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