A sequence of numbers is given as: 1, 2, 2, 3, 3, 3, 4, 4, 4, 4 and so
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19 May 2024, 23:02
Of course . Using observation and logic.
Notice how the sequence has as first term 1 then 2 but two times and then three three times , 4 four times............until k which is the 100 terms
This mean that using the formula for sum of an arithmetic progression we can find easily the solution
\(\frac{k(k+1)}{2}\) why ? every term after the previous June is oNE more
Picking number for example C we do have 13*14/2=91 and the answer is D or E
We need a value a bit bigger (100) so the answer is D