Finding the Fourth Proportional to 76,406.72, 105,442.24 and 42,872

Step by Step Solution

1. Step 1: Write the proportion equation
   76,406.72 : 105,442.24 = 42,872 : x
2. Step 2: Convert to fraction form
   76,406.72/105,442.24 = 42,872/x
3. Step 3: Cross multiply
   76,406.72x = 105,442.24 × 42,872
4. Step 4: Simplify right side
   76,406.72x = 4,520,519,713.28
5. Step 5: Solve for x
   x = 4,520,519,713.28/76,406.72
6. Step 6: Final answer
   x = 59,163.90