Finding the Fourth Proportional to 99,152.96, 136,792.16 and 56,688.72

Step by Step Solution

1. Step 1: Write the proportion equation
   99,152.96 : 136,792.16 = 56,688.72 : x
2. Step 2: Convert to fraction form
   99,152.96/136,792.16 = 56,688.72/x
3. Step 3: Cross multiply
   99,152.96x = 136,792.16 × 56,688.72
4. Step 4: Simplify right side
   99,152.96x = 7,754,572,456.44
5. Step 5: Solve for x
   x = 7,754,572,456.44/99,152.96
6. Step 6: Final answer
   x = 78,208.18