Here is the problem. The numbers on people with albinism vary widely. I've read studies that say there are 18,000, and about 12 years ago the World Health Organization came up with 170,000.
The problem is that none of these people have substantiated how they create the calculations. The fact is that we really don't know exactly how many people with albinism there are in Tanzania. Even the one in 1,000 figure is a guesstimate.
Dr. Murray Brilliant is a U.S. geneticist who has done a little bit of study on the origins of albinism and its occurrence in east Africa. His best guessed estimate, based on limited anecdotal observation, is that it's one in 1,000. So you're correct that if that figure were accurate there would be 44,000. But we're not certain that figure is accurate. There may be communities within Tanzania where one in 100 has albinism.
So your guess is as good as mine, but that's certainly safe to go with. I would say at minimum there are 44,000.