Find the number of ways, in which 10 boys can form a ring?

Answer

To find the number of ways in which 10 boys can form a ring, we can follow these steps:

### Step 1: Understand Circular Permutations
In circular permutations, the arrangement is considered the same if it can be rotated into another arrangement. Therefore, the formula for the number of ways to arrange \( n \) objects in a circle is given by \( (n-1)! \).

### Step 2: Identify the Number of Boys
In this problem, we have \( n = 10 \) boys.

### Step 3: Apply the Formula
Using the formula for circular permutations:
\[ \text{Number of ways} = (n-1)! = (10-1)! = 9! \]

### Step 4: Calculate \( 9! \)
Now we need to calculate \( 9! \):
\[ 9! = 9 \times 8 \times 7 \times 6 \times 5 \times 4 \times 3 \times 2 \times 1 = 362880 \]

### Final Answer
Thus, the number of ways in which 10 boys can form a ring is:
\[ \boxed{362880} \]

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