Finding the Fourth Proportional to 72,386.78, 99,940.35 and 58,990.05

Step by Step Solution

1. Step 1: Write the proportion equation
   72,386.78 : 99,940.35 = 58,990.05 : x
2. Step 2: Convert to fraction form
   72,386.78/99,940.35 = 58,990.05/x
3. Step 3: Cross multiply
   72,386.78x = 99,940.35 × 58,990.05
4. Step 4: Simplify right side
   72,386.78x = 5,895,486,243.52
5. Step 5: Solve for x
   x = 5,895,486,243.52/72,386.78
6. Step 6: Final answer
   x = 81,444.25