Finding the Fourth Proportional to 3,915.72, 5,415.71 and 3,850.11

Step by Step Solution

1. Step 1: Write the proportion equation
   3,915.72 : 5,415.71 = 3,850.11 : x
2. Step 2: Convert to fraction form
   3,915.72/5,415.71 = 3,850.11/x
3. Step 3: Cross multiply
   3,915.72x = 5,415.71 × 3,850.11
4. Step 4: Simplify right side
   3,915.72x = 20,851,059.98
5. Step 5: Solve for x
   x = 20,851,059.98/3,915.72
6. Step 6: Final answer
   x = 5,324.96