Finding the Fourth Proportional to 101,441.31, 139,980.20 and 56,118.57

Step by Step Solution

1. Step 1: Write the proportion equation
   101,441.31 : 139,980.20 = 56,118.57 : x
2. Step 2: Convert to fraction form
   101,441.31/139,980.20 = 56,118.57/x
3. Step 3: Cross multiply
   101,441.31x = 139,980.20 × 56,118.57
4. Step 4: Simplify right side
   101,441.31x = 7,855,488,371.72
5. Step 5: Solve for x
   x = 7,855,488,371.72/101,441.31
6. Step 6: Final answer
   x = 77,438.75