When primals were first introduced people conducted tests with thousands of items and they got results between 0.22% and 0.25% for primals, i.e. However, your assertion that 10% of ancients are primals would mean that the chance of primals would be 1 in 100, or 1%.

Now, whilst Blizzard have actually stated that the chance of a legendary being an ancient is 1 in 10, they have never actually stated the chance of a primal.

According to the law, the average of the results obtained from a large number of trials should be close to the expected value, and will tend to become closer to the expected value as more trials are performed. Equip one, and keep reforging the other until you get a better roll/ancient/primal. Generally, you upgrade yellows until you get the item you want. In probability theory, the law of large numbers (LLN) is a theorem that describes the result of performing the same experiment a large number of times. Reforging a legendary costs a pretty penny, but at least you are guaranteed to get the same item back. Well, statistically speaking, the figures I used were known as Expected Values, which is a specific term from the Law of Large Numbers. And dont say 40 in 400 are ancient … learn what chance is … statistically speaking, there is 10% for ancient and 10% from that for primal

Diablo 3 reforge legendary primal