Finding the Fourth Proportional to 128,969.19, 177,993.86 and 72,380.52

Step by Step Solution

1. Step 1: Write the proportion equation
   128,969.19 : 177,993.86 = 72,380.52 : x
2. Step 2: Convert to fraction form
   128,969.19/177,993.86 = 72,380.52/x
3. Step 3: Cross multiply
   128,969.19x = 177,993.86 × 72,380.52
4. Step 4: Simplify right side
   128,969.19x = 12,883,287,781.70
5. Step 5: Solve for x
   x = 12,883,287,781.70/128,969.19
6. Step 6: Final answer
   x = 99,894.31