Finding the Fourth Proportional to 101,117.50, 139,542.15 and 56,405.50

Step by Step Solution

1. Step 1: Write the proportion equation
   101,117.50 : 139,542.15 = 56,405.50 : x
2. Step 2: Convert to fraction form
   101,117.50/139,542.15 = 56,405.50/x
3. Step 3: Cross multiply
   101,117.50x = 139,542.15 × 56,405.50
4. Step 4: Simplify right side
   101,117.50x = 7,870,944,741.83
5. Step 5: Solve for x
   x = 7,870,944,741.83/101,117.50
6. Step 6: Final answer
   x = 77,839.59