Finding the Fourth Proportional to 105,661.29, 145,813.59 and 57,915.57

Step by Step Solution

1. Step 1: Write the proportion equation
   105,661.29 : 145,813.59 = 57,915.57 : x
2. Step 2: Convert to fraction form
   105,661.29/145,813.59 = 57,915.57/x
3. Step 3: Cross multiply
   105,661.29x = 145,813.59 × 57,915.57
4. Step 4: Simplify right side
   105,661.29x = 8,444,877,178.60
5. Step 5: Solve for x
   x = 8,444,877,178.60/105,661.29
6. Step 6: Final answer
   x = 79,924.04