High one mathematics ~ arithmetic series solution, thank you! In the arithmetic sequence {an}, S10 = 120, then the value of A2 + A9 is? Brother on the first floor, can you be more detailed? I really don't understand!

A because 1 + A10 = A2 + A9 = A3 + A8 = A4 + A7 = 2a5, so S10 = 5 (A2 + A9) so A2 + A9 = 24

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