Finding the Fourth Proportional to 101,217.50, 139,680.16 and 56,505.50

Step by Step Solution

1. Step 1: Write the proportion equation
   101,217.50 : 139,680.16 = 56,505.50 : x
2. Step 2: Convert to fraction form
   101,217.50/139,680.16 = 56,505.50/x
3. Step 3: Cross multiply
   101,217.50x = 139,680.16 × 56,505.50
4. Step 4: Simplify right side
   101,217.50x = 7,892,697,280.88
5. Step 5: Solve for x
   x = 7,892,697,280.88/101,217.50
6. Step 6: Final answer
   x = 77,977.60