Finding the Fourth Proportional to 76,780.78, 105,955.86 and 42,789.10

Step by Step Solution

1. Step 1: Write the proportion equation
   76,780.78 : 105,955.86 = 42,789.10 : x
2. Step 2: Convert to fraction form
   76,780.78/105,955.86 = 42,789.10/x
3. Step 3: Cross multiply
   76,780.78x = 105,955.86 × 42,789.10
4. Step 4: Simplify right side
   76,780.78x = 4,533,755,889.13
5. Step 5: Solve for x
   x = 4,533,755,889.13/76,780.78
6. Step 6: Final answer
   x = 59,048.06