Finding the Fourth Proportional to 8,731.16, 13,091.86 and 5,174.72

Step by Step Solution

1. Step 1: Write the proportion equation
   8,731.16 : 13,091.86 = 5,174.72 : x
2. Step 2: Convert to fraction form
   8,731.16/13,091.86 = 5,174.72/x
3. Step 3: Cross multiply
   8,731.16x = 13,091.86 × 5,174.72
4. Step 4: Simplify right side
   8,731.16x = 67,746,709.78
5. Step 5: Solve for x
   x = 67,746,709.78/8,731.16
6. Step 6: Final answer
   x = 7,759.19