Решение
<span>b1= - 64 i q = -1/2.
Sn = [b</span>₁(1 - q^n)] / (1 - q)
bn = b₁ * q^(n - 1)
b₆ = (- 64) * (- 1/2)⁵ = 64/32 = 2
S₅ = [(- 64) * (1 - (-1/2)⁶] / [1 - (- 1/2)] = [- 64*(1 - 1/64)] / (1 + 1/2) =
= [- 64 * (63/64)] / (3/2) = (- 63 * 2) / 3 = - 21 * 2 = - 42
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X- муж, y- жен
{1100=x+y
{1130=0,8*x+1,3*y
x=1100-y
1130=0,8*(1100-y)+1,3*y
1130=880-0,8*y+1,3*y
250=0,5*y
y=500 x=600
Наверное вот так
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