Finding the Fourth Proportional to 105,476.87, 145,558.46 and 57,078.79

Step by Step Solution

1. Step 1: Write the proportion equation
   105,476.87 : 145,558.46 = 57,078.79 : x
2. Step 2: Convert to fraction form
   105,476.87/145,558.46 = 57,078.79/x
3. Step 3: Cross multiply
   105,476.87x = 145,558.46 × 57,078.79
4. Step 4: Simplify right side
   105,476.87x = 8,308,300,485.67
5. Step 5: Solve for x
   x = 8,308,300,485.67/105,476.87
6. Step 6: Final answer
   x = 78,768.94