Finding the Fourth Proportional to 101,309.78, 139,810.29 and 55,990.70

Step by Step Solution

1. Step 1: Write the proportion equation
   101,309.78 : 139,810.29 = 55,990.70 : x
2. Step 2: Convert to fraction form
   101,309.78/139,810.29 = 55,990.70/x
3. Step 3: Cross multiply
   101,309.78x = 139,810.29 × 55,990.70
4. Step 4: Simplify right side
   101,309.78x = 7,828,076,004.30
5. Step 5: Solve for x
   x = 7,828,076,004.30/101,309.78
6. Step 6: Final answer
   x = 77,268.71