Finding the Fourth Proportional to 128,401.37, 177,199.10 and 71,039.69

Step by Step Solution

1. Step 1: Write the proportion equation
   128,401.37 : 177,199.10 = 71,039.69 : x
2. Step 2: Convert to fraction form
   128,401.37/177,199.10 = 71,039.69/x
3. Step 3: Cross multiply
   128,401.37x = 177,199.10 × 71,039.69
4. Step 4: Simplify right side
   128,401.37x = 12,588,167,891.09
5. Step 5: Solve for x
   x = 12,588,167,891.09/128,401.37
6. Step 6: Final answer
   x = 98,037.65