The arithmetic progression is given by the condition an = −0.6 + 8.6n. Find the sum of its first 10 members.

1) Find a1, for this we substitute the value 1 for n in the formula an = −0.6 + 8.6 * n: a1 = -0.6 + 8.6 * 1 = -0.6 + 8.6 = 8 ;

2) Find a10, for this we substitute 10 instead of n in the formula an = −0.6 + 8.6 * n: a10 = -0.6 + 8.6 * 10 = -0.6 + 8.6 * 10 = 85.4;

3) Using the formula Sn = ((a1 + an) / 2) * n, we find the sum of the first 10 members of the arithmetic progression: S10 = ((8 + 85.4) / 2) * 10 = 93.4 / 2 * 10 = 46 , 7 * 10 = 467.

Answer: 467.



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