I'm playing a deck that needs to hit that 2nd land quite consistently. Any lands past 4 turn into more or less dead, weak draws. If I'm playing 4 Serum Visions and no other mana producing things, how many lands should I be running?

Some math:

If I'm running 21 lands, then the deck consists of 35% lands (21/60), meaning 65% of the deck are non-lands.

Serum Visions digs 3 deep. To work out the probability of Serum Visions missing a land: 0.65*0.65*0.65=0.275.

Therefore, Serum Visions equates to 0.725 of a land when running 21 lands. 4 Serum Visions is approximately equivalent to 3 lands. So when running 21 lands with 4 Serum Visions, one is almost playing essentially 24 lands.

This is a rather useful tool for this sort of thing:

http://stattrek.com/online-calculato...geometric.aspx

Using a population of 59, number of successes in population of 24, sample size of 8 and number of successes of 2, it tells me that one will hit 2 or greater 92% of the time. 23 lands is 90%.

I quickly did the math and found when running 20 lands, Serum Visions equates to 0.7 of a land, compared to 0.75.

Now I'm curious, adding that extra land gives one about an extra 2% chance of hitting that 2nd land on time, but what sort of impact will it have on flooding? This is more difficult to calculate, but I can do a rough calculation:

Population: 59

Number of successes: 24

Sample size: 10 (T4 on the play without drawing)

Number of successes: 4

4 or greater equates to a 65% chance of occurring, pretty friggin huge. 23 lands instead equates to a 60% chance of occuring.

So when comparing 23 lands to 24, the extra land drop causes one to hit the 2nd land 2% more often, and also causes one to flood 5% more often. I also play Remands in the deck, which will make this later effect worse.

So because of this, could I reason that 20 lands, with 4 serum visions, is where I want to be?