IPMAT Indore 2024Algebra > Medium4576✅ Correct Option: 2Related questions:Let S1={100,105,110,115,...}S_1 = \{100, 105, 110, 115, ... \}S1={100,105,110,115,...} and S2={100,95,90,85,...}S_2 = \{100, 95, 90, 85, ... \}S2={100,95,90,85,...} be two series in arithmetic progression. If aka_kak and bkb_kbk are the kkk-th terms of S1S_1S1 and S2S_2S2, respectively, then ∑k=120akbk\sum_{k=1}^{20} a_k b_k∑k=120akbk equals __________.The sum up to 101010 terms of the series 1⋅3+5⋅7+9⋅11+...1 \cdot 3 + 5 \cdot 7 + 9 \cdot 11 + ...1⋅3+5⋅7+9⋅11+... isA new sequence is obtained from the sequence of positive integers (1,2,3,…)(1,2,3, \ldots)(1,2,3,…) by deleting all the perfect squares. Then the 2022nd 2022^{\text {nd }}2022nd term of the new sequence is ________.