Answer:
225.78 grams
Step-by-step explanation:
To solve this question, we would be using the formula
P(t) = Po × 2^t/n
Where P(t) = Remaining amount after r hours
Po = Initial amount
t = Time
In the question,
Where P(t) = Remaining amount after r hours = unknown
Po = Initial amount = 537
t = Time = 10 days
P(t) = 537 × 2^(10/)
P(t) = 225.78 grams
Therefore, the amount of iodine-131 left after 10 days = 225.78 grams
Permutation: In a race of 10 students, find the number of ways students can finish 1st, 2nd, and 3rd. In this case the order matters, so it is a permutation.
10 x 9 x 8 = 720 ways
Combination: In a class of 10 students, find the number of ways a group of 3 students can be selected to win a prize. In this case the order doesn't matter, so it's a combination.
10 x 9 x 8 / (3 x 2 x 1) = 120 ways
