Finding the Fourth Proportional to 21,017.28, 31,535.67 and 8,545.86

Step by Step Solution

1. Step 1: Write the proportion equation
   21,017.28 : 31,535.67 = 8,545.86 : x
2. Step 2: Convert to fraction form
   21,017.28/31,535.67 = 8,545.86/x
3. Step 3: Cross multiply
   21,017.28x = 31,535.67 × 8,545.86
4. Step 4: Simplify right side
   21,017.28x = 269,499,420.83
5. Step 5: Solve for x
   x = 269,499,420.83/21,017.28
6. Step 6: Final answer
   x = 12,822.75