Finding the Fourth Proportional to 105,456, 145,524.61 and 57,711.36

Step by Step Solution

1. Step 1: Write the proportion equation
   105,456 : 145,524.61 = 57,711.36 : x
2. Step 2: Convert to fraction form
   105,456/145,524.61 = 57,711.36/x
3. Step 3: Cross multiply
   105,456x = 145,524.61 × 57,711.36
4. Step 4: Simplify right side
   105,456x = 8,398,423,156.57
5. Step 5: Solve for x
   x = 8,398,423,156.57/105,456
6. Step 6: Final answer
   x = 79,639.12