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Q61Section C (Part C)61 of 120

Real numbers — digits of a sequence approaching a terminating decimal

Let α=∑ℓ=12025aℓ10ℓ\alpha=\sum_{\ell=1}^{2025}\dfrac{a_{\ell}}{10^{\ell}} with aℓ∈{0,1,…,9}a_{\ell}\in\{0,1,…,9\} for all 1≤ℓ≤20251\le\ell\le2025 and a2025≠0a_{2025}\neq0. Let (βn)n≥1(\beta_n)_{n\ge1} be a strictly increasing sequence of positive real numbers in (0,1)(0,1) that converges to α\alpha. For each n≥1n\ge1, write βn=∑ℓ=1∞bn,ℓ10ℓ\beta_n=\sum_{\ell=1}^{\infty}\dfrac{b_{n,\ell}}{10^{\ell}} with bn,ℓ∈{0,1,…,9}b_{n,\ell}\in\{0,1,…,9\}, for the infinite decimal expansion of βn\beta_n. Which of the following statements are necessarily true?

Multiple select: one or more options are correct. Select all of them, then submit — marks need the exact set.

Options

Select every correct option, then submit.