Finding the Fourth Proportional to 8,709.16, 12,018.30 and 5,172.28

Step by Step Solution

1. Step 1: Write the proportion equation
   8,709.16 : 12,018.30 = 5,172.28 : x
2. Step 2: Convert to fraction form
   8,709.16/12,018.30 = 5,172.28/x
3. Step 3: Cross multiply
   8,709.16x = 12,018.30 × 5,172.28
4. Step 4: Simplify right side
   8,709.16x = 62,162,012.72
5. Step 5: Solve for x
   x = 62,162,012.72/8,709.16
6. Step 6: Final answer
   x = 7,137.54