The half-life of a radioactive kind of antimony is 4 days. How much will be left after 12 days, if you start with 7,600 grams of it?

Sure, here's how you can solve this problem:

1. First, understand that half-life is the time it takes for half of the radioactive substance to decay. In this case, the half-life of antimony is 4 days.

2. After one half-life (4 days), half of the original amount will be left. So, after 4 days, you will have 7,600 / 2 = 3,800 grams of antimony left.

3. After two half-lives (8 days), half of the remaining amount will decay. So, after 8 days, you will have 3,800 / 2 = 1,900 grams of antimony left.

4. After three half-lives (12 days), half of the remaining amount will decay. So, after 12 days, you will have 1,900 / 2 = 950 grams of antimony left.

So, after 12 days, you will have 950 grams of antimony left.