Finding the Fourth Proportional to 105,621.10, 145,760.50 and 57,877.50

Step by Step Solution

1. Step 1: Write the proportion equation
   105,621.10 : 145,760.50 = 57,877.50 : x
2. Step 2: Convert to fraction form
   105,621.10/145,760.50 = 57,877.50/x
3. Step 3: Cross multiply
   105,621.10x = 145,760.50 × 57,877.50
4. Step 4: Simplify right side
   105,621.10x = 8,436,253,338.75
5. Step 5: Solve for x
   x = 8,436,253,338.75/105,621.10
6. Step 6: Final answer
   x = 79,872.80