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Let a_1, a_2, a_3,… ,a_49 be in A.P. such that Σ _ k⁡ = 0 ^ 1 2 a_4k+1=416 and a_9+a_43=66. If a_1^2+a_2^2+… +a_17^2=140m, then m is equal to:

JEE Main 2018 — Mathematics Algebra

2018mcqmedium

Let a1,a2,a3,……,a49{a}_{1}, {a}_{2}, {a}_{3},\ldots \ldots ,{a}_{49}a1​,a2​,a3​,……,a49​ be in A.P.A.P.A.P. such that Σk⁡=012a4k+1=416\Sigma _{ k⁡ = 0 }^{ 1 2 } {a}_{4k+1}=416Σk⁡=012​a4k+1​=416 and a9+a43=66.{a}_{9}+{a}_{43}=66.a9​+a43​=66. If a12+a22+…+a172=140m,{a}_{1}^{2}+{a}_{2}^{2}+\ldots +{a}_{17}^{2}=140m,a12​+a22​+…+a172​=140m, then mmm is equal to:

Official previous-year question

Held on 8 Apr 2018 · Verified 6 Jul 2026.

Options

  1. A

    333333

  2. B

    666666

  3. C

    686868

  4. D

    343434

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