Finding the Fourth Proportional to 128,520.72, 177,356.76 and 71,154.54

Step by Step Solution

1. Step 1: Write the proportion equation
   128,520.72 : 177,356.76 = 71,154.54 : x
2. Step 2: Convert to fraction form
   128,520.72/177,356.76 = 71,154.54/x
3. Step 3: Cross multiply
   128,520.72x = 177,356.76 × 71,154.54
4. Step 4: Simplify right side
   128,520.72x = 12,619,738,673.69
5. Step 5: Solve for x
   x = 12,619,738,673.69/128,520.72
6. Step 6: Final answer
   x = 98,192.25