Finding the Fourth Proportional to 10,915.20, 16,397.10 and 10,502.10

Step by Step Solution

1. Step 1: Write the proportion equation
   10,915.20 : 16,397.10 = 10,502.10 : x
2. Step 2: Convert to fraction form
   10,915.20/16,397.10 = 10,502.10/x
3. Step 3: Cross multiply
   10,915.20x = 16,397.10 × 10,502.10
4. Step 4: Simplify right side
   10,915.20x = 172,203,983.91
5. Step 5: Solve for x
   x = 172,203,983.91/10,915.20
6. Step 6: Final answer
   x = 15,776.53