Q.

Let Sn=12+222+32+242+52+262+...'n'  terms . Column-II contains the units digit of the term given in Column-I.

 Column-I Column-II
(I)3S2024506(P)6
(II)3S2023506(Q)4
(III)6S20221011(R)0
(IV)6S20211011(S)2

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a

(I)-(R); (II)-(R); (III)-(S); (IV)-(P) 

b

(I)-(R); (II)-(Q); (III)-(Q); (IV)-(P)

c

(I)-(Q); (II)-(R); (III)-(S); (IV)-(R)

d

(I)-(Q); (II)-(P); (III)-(S); (IV)-(R)

answer is B.

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Detailed Solution

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 Sn=(12+22+32........)+(22+42+62.....)=S1+S2
Case (I): When ‘n’ is even say n=2m, mN  In this S1  contains m terms and S2 contain m terms 
Sn=n(n+1)(2n+1)6+n(n+2)(n+1)6=n(n+1)22 
Case (II): When ‘n’ is odd say n=2m+1, mN  In this  S1  contains (m+1) terms and S2  contain m terms 
Sn=n(n+1)(2n+1)6+(n21)(n)6=n2(n+1)2 

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Let Sn=12+2⋅22+32+2⋅42+52+2⋅62+...'n'  terms . Column-II contains the units digit of the term given in Column-I. Column-I Column-II(I)3S2024506(P)6(II)3S2023506(Q)4(III)6S20221011(R)0(IV)6S20211011(S)2