Finding the Fourth Proportional to 76,658.78, 105,788.31 and 42,666.77

Step by Step Solution

1. Step 1: Write the proportion equation
   76,658.78 : 105,788.31 = 42,666.77 : x
2. Step 2: Convert to fraction form
   76,658.78/105,788.31 = 42,666.77/x
3. Step 3: Cross multiply
   76,658.78x = 105,788.31 × 42,666.77
4. Step 4: Simplify right side
   76,658.78x = 4,513,644,962.52
5. Step 5: Solve for x
   x = 4,513,644,962.52/76,658.78
6. Step 6: Final answer
   x = 58,879.69