Finding the Fourth Proportional to 99,691.89, 137,583 and 56,684.88

Step by Step Solution

1. Step 1: Write the proportion equation
   99,691.89 : 137,583 = 56,684.88 : x
2. Step 2: Convert to fraction form
   99,691.89/137,583 = 56,684.88/x
3. Step 3: Cross multiply
   99,691.89x = 137,583 × 56,684.88
4. Step 4: Simplify right side
   99,691.89x = 7,798,875,845.04
5. Step 5: Solve for x
   x = 7,798,875,845.04/99,691.89
6. Step 6: Final answer
   x = 78,229.79