Scroll probability formula

I hope you guys don't mind me adding to this and bumping this topic.

Scroll probability can be easily calculated using binomial distribution, in particular, the probability mass formula "." The first part (n,k) or n chooses k, is the binomial coefficient, which can be calculated with the formula "".

Using Excel, I made some basic chart graphics to visualize the probability mass function. The following scenarios are for an overall with 10 slots, using 10%, 30%, 50%, 60% and 70% scrolls.

Success rate (10%)

number of successes percentage rate
0 34.87%
1 38.74%
2 19.37%
3 5.74%
4 1.12%
5 0.15%
6 0.01%
7 0.00%
8 0.00%
9 0.00%
10 0.00%

 Spoiler

Success rate (30%)

number of successes percentage rate
0 2.82%
1 12.11%
2 23.35%
3 26.68%
4 20.01%
5 10.29%
6 3.68%
7 0.90%
8 0.14%
9 0.01%
10 0.00%

 Spoiler

Success rate (50%)

number of successes percentage rate
0 0.10%
1 0.98%
2 4.39%
3 11.72%
4 20.51%
5 24.61%
6 20.51%
7 11.72%
8 4.39%
9 0.98%
10 0.10%

 Spoiler

Success rate (60%)

number of successes percentage rate
0 0.01%
1 0.16%
2 1.06%
3 4.25%
4 11.15%
5 20.07%
6 25.08%
7 21.50%
8 12.09%
9 4.03%
10 0.60%

 Spoiler

Success rate (70%)

number of successes percentage rate
0 0.00%
1 0.01%
2 0.14%
3 0.90%
4 3.68%
5 10.29%
6 20.01%
7 26.68%
8 23.35%
9 12.11%
10 2.82%

 Spoiler

Point out any errors, if you see any.

The formula you posted is esentially a more statistic-savvy version of what I came up with. But still. looks good.