Finding the Fourth Proportional to 128,016.48, 191,993.76 and 56,899.92

Step by Step Solution

1. Step 1: Write the proportion equation
   128,016.48 : 191,993.76 = 56,899.92 : x
2. Step 2: Convert to fraction form
   128,016.48/191,993.76 = 56,899.92/x
3. Step 3: Cross multiply
   128,016.48x = 191,993.76 × 56,899.92
4. Step 4: Simplify right side
   128,016.48x = 10,924,429,584.50
5. Step 5: Solve for x
   x = 10,924,429,584.50/128,016.48
6. Step 6: Final answer
   x = 85,336.12