Finding the Fourth Proportional to 72,990.31, 100,726.77 and 39,456.31

Step by Step Solution

1. Step 1: Write the proportion equation
   72,990.31 : 100,726.77 = 39,456.31 : x
2. Step 2: Convert to fraction form
   72,990.31/100,726.77 = 39,456.31/x
3. Step 3: Cross multiply
   72,990.31x = 100,726.77 × 39,456.31
4. Step 4: Simplify right side
   72,990.31x = 3,974,306,662.42
5. Step 5: Solve for x
   x = 3,974,306,662.42/72,990.31
6. Step 6: Final answer
   x = 54,449.78