Finding the Fourth Proportional to 78,449.59, 108,260.57 and 42,639.50

Step by Step Solution

1. Step 1: Write the proportion equation
   78,449.59 : 108,260.57 = 42,639.50 : x
2. Step 2: Convert to fraction form
   78,449.59/108,260.57 = 42,639.50/x
3. Step 3: Cross multiply
   78,449.59x = 108,260.57 × 42,639.50
4. Step 4: Simplify right side
   78,449.59x = 4,616,176,711.92
5. Step 5: Solve for x
   x = 4,616,176,711.92/78,449.59
6. Step 6: Final answer
   x = 58,842.59