Finding the Fourth Proportional to 71,990.43, 99,345.83 and 40,159.86

Step by Step Solution

1. Step 1: Write the proportion equation
   71,990.43 : 99,345.83 = 40,159.86 : x
2. Step 2: Convert to fraction form
   71,990.43/99,345.83 = 40,159.86/x
3. Step 3: Cross multiply
   71,990.43x = 99,345.83 × 40,159.86
4. Step 4: Simplify right side
   71,990.43x = 3,989,714,423.58
5. Step 5: Solve for x
   x = 3,989,714,423.58/71,990.43
6. Step 6: Final answer
   x = 55,420.07