Finding the Fourth Proportional to 128,970.88, 177,987.71 and 72,382.25

Step by Step Solution

1. Step 1: Write the proportion equation
   128,970.88 : 177,987.71 = 72,382.25 : x
2. Step 2: Convert to fraction form
   128,970.88/177,987.71 = 72,382.25/x
3. Step 3: Cross multiply
   128,970.88x = 177,987.71 × 72,382.25
4. Step 4: Simplify right side
   128,970.88x = 12,883,150,922.15
5. Step 5: Solve for x
   x = 12,883,150,922.15/128,970.88
6. Step 6: Final answer
   x = 99,891.94