Finding the Fourth Proportional to 105,571.80, 145,689.57 and 57,825

Step by Step Solution

1. Step 1: Write the proportion equation
   105,571.80 : 145,689.57 = 57,825 : x
2. Step 2: Convert to fraction form
   105,571.80/145,689.57 = 57,825/x
3. Step 3: Cross multiply
   105,571.80x = 145,689.57 × 57,825
4. Step 4: Simplify right side
   105,571.80x = 8,424,499,385.25
5. Step 5: Solve for x
   x = 8,424,499,385.25/105,571.80
6. Step 6: Final answer
   x = 79,798.77