What is the difference between the sum of the first 20 terms and the next 20 terms of the arithmetic sequence 6, 10, 14, …?

For the arithmetic sequence,

a = 6

d = 10-6 = 4

S_n = …(eq)1

Sum of first 20 terms = S₂₀

Sum of next 20 terms = S₄₀-s₂₀

Substituting values in eq1

S₂₀ =

= 10× 88

= 880

S₄₀ =

= 20× 168

= 3360

Sum of first 20 terms = S₂₀ = 880

Sum of next 20 terms = S₄₀-s₂₀ = 3360-880 = 2480

∴ Difference between sum of first 20 terms = 2480-880 = 1600

And next 20 terms

Hence, answer is found out.