RRB Technician (Grade I Signal + Grade III) 2026 · Question 207 of 265

What should come in place of ‘?’ in the given series? 7 21 63 189 567 ?

Answer: D. 1701

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Source: RRB Technician Grade III 10-Mar-2026 Shift 3 (oliveboard compilation with answer key) · reliable-secondary

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