Final answer:
The student initially had 36 rare coins. After doubling the collection by obtaining 36 more coins, there are now a total of 72 coins in the student’s collection.
Step-by-step explanation:
The student's question is about how to determine the current number of coins in a collection after the collection has doubled in size.
Let's denote the initial number of coins the student had as x. According to the question, the student has obtained 36 more coins than he started with, and this resulted in doubling the collection. Hence, we can write an equation:
x + 36 = 2x
Now, solving for x, we subtract x from both sides:
x + 36 - x = 2x - x
36 = x
The initial number of coins was 36. Since the collection has doubled, the current number of coins is:
2 * 36 = 72
Therefore, there are currently 72 coins in the collection.