The study group members (8 males and 4 females) took three probiotic containing capsules (8.4 log CFU per capsule) two times daily (the daily dose 9.2 log CFU) during three weeks.
So, the study protocol says the active group took 6 capsules a day.
The question says that the retail version of this capsule says it contains 8 billion CFU per capsule. So, without knowing the weight of the bacteria in the capsule, it's not possible to do a direct comparison as bacteria are normally counted as the ability to form colonies per g, or per ml of the bacterium. And then because these figures are very high, they are changed to a log base 10.