The selling unit price of these mushrooms =10+0.1x.

The sales volume of these mushrooms = 6000- 10x.

(2) If it is stored for X days, the selling price for one-time sale is 100000 yuan (0≤x≤ 1 10).

Then, (10+0.1x) (6000-1x) =100000.

Which is x? -500x+40000=0

That is (x- 100) (x-400) = 0.

Because, 0≤x≤ 1 10.

Then, X- 100 = 0.

Solution, x = 100

Therefore, after the mushrooms were stored for 65,438+000 days, the sales price obtained by one-time sales was 65,438+000,000 yuan.

(3) If it is stored for x days, the maximum profit can be obtained by selling it at one time (0≤x≤ 1 10).

Profit = sales price-cost-expense

=( 10+0. 1x)(6000- 10x)-6000× 10-240 x

=-x？ +260 times

=-(x- 130)？ + 16900

Because, 0≤x≤ 1 10.

Then when x = 1 10, the maximum profit is = 16500 yuan.

Therefore, after mushroom is stored for 1 10 days, the maximum profit can be obtained by selling it once.