Finding the Fourth Proportional to 101,128.80, 139,556.82 and 55,807.20

Step by Step Solution

1. Step 1: Write the proportion equation
   101,128.80 : 139,556.82 = 55,807.20 : x
2. Step 2: Convert to fraction form
   101,128.80/139,556.82 = 55,807.20/x
3. Step 3: Cross multiply
   101,128.80x = 139,556.82 × 55,807.20
4. Step 4: Simplify right side
   101,128.80x = 7,788,275,365.10
5. Step 5: Solve for x
   x = 7,788,275,365.10/101,128.80
6. Step 6: Final answer
   x = 77,013.43