Finding the Fourth Proportional to 8,472.21, 12,773.31 and 7,900.54

Step by Step Solution

1. Step 1: Write the proportion equation
   8,472.21 : 12,773.31 = 7,900.54 : x
2. Step 2: Convert to fraction form
   8,472.21/12,773.31 = 7,900.54/x
3. Step 3: Cross multiply
   8,472.21x = 12,773.31 × 7,900.54
4. Step 4: Simplify right side
   8,472.21x = 100,916,029.47
5. Step 5: Solve for x
   x = 100,916,029.47/8,472.21
6. Step 6: Final answer
   x = 11,911.41