Finding the Fourth Proportional to 128,702.76, 177,609.69 and 72,114.54

Step by Step Solution

1. Step 1: Write the proportion equation
   128,702.76 : 177,609.69 = 72,114.54 : x
2. Step 2: Convert to fraction form
   128,702.76/177,609.69 = 72,114.54/x
3. Step 3: Cross multiply
   128,702.76x = 177,609.69 × 72,114.54
4. Step 4: Simplify right side
   128,702.76x = 12,808,241,093.89
5. Step 5: Solve for x
   x = 12,808,241,093.89/128,702.76
6. Step 6: Final answer
   x = 99,518.00