How many milligrams of an initial 63 of calcium-47 remain after 27?

Answer 1

To determine how much calcium-47 remains after 27 days, we need to know its half-life, which is about 4.5 days. After 27 days, which is approximately 6 half-lives, the amount remaining can be calculated using the formula: ( \text{remaining} = \text{initial} \times \left( \frac{1}{2} \right)^{\text{number of half-lives}} ). Therefore, starting with 63 mg, the calculation would be ( 63 \times \left( \frac{1}{2} \right)^6 ), resulting in approximately 0.98 mg remaining.