Finding the Fourth Proportional to 21,025.98, 31,544.46 and 7,878.60

Step by Step Solution

1. Step 1: Write the proportion equation
   21,025.98 : 31,544.46 = 7,878.60 : x
2. Step 2: Convert to fraction form
   21,025.98/31,544.46 = 7,878.60/x
3. Step 3: Cross multiply
   21,025.98x = 31,544.46 × 7,878.60
4. Step 4: Simplify right side
   21,025.98x = 248,526,182.56
5. Step 5: Solve for x
   x = 248,526,182.56/21,025.98
6. Step 6: Final answer
   x = 11,819.96