Finding the Fourth Proportional to 99,150.96, 136,789.40 and 56,686.72

Step by Step Solution

1. Step 1: Write the proportion equation
   99,150.96 : 136,789.40 = 56,686.72 : x
2. Step 2: Convert to fraction form
   99,150.96/136,789.40 = 56,686.72/x
3. Step 3: Cross multiply
   99,150.96x = 136,789.40 × 56,686.72
4. Step 4: Simplify right side
   99,150.96x = 7,754,142,416.77
5. Step 5: Solve for x
   x = 7,754,142,416.77/99,150.96
6. Step 6: Final answer
   x = 78,205.42