Finding the Fourth Proportional to 56,631.43, 78,153.39 and 31,139.74

Step by Step Solution

1. Step 1: Write the proportion equation
   56,631.43 : 78,153.39 = 31,139.74 : x
2. Step 2: Convert to fraction form
   56,631.43/78,153.39 = 31,139.74/x
3. Step 3: Cross multiply
   56,631.43x = 78,153.39 × 31,139.74
4. Step 4: Simplify right side
   56,631.43x = 2,433,676,276.72
5. Step 5: Solve for x
   x = 2,433,676,276.72/56,631.43
6. Step 6: Final answer
   x = 42,973.95