Finding the Fourth Proportional to 139,710.48, 209,567.64 and 39,870.62

Step by Step Solution

1. Step 1: Write the proportion equation
   139,710.48 : 209,567.64 = 39,870.62 : x
2. Step 2: Convert to fraction form
   139,710.48/209,567.64 = 39,870.62/x
3. Step 3: Cross multiply
   139,710.48x = 209,567.64 × 39,870.62
4. Step 4: Simplify right side
   139,710.48x = 8,355,591,738.74
5. Step 5: Solve for x
   x = 8,355,591,738.74/139,710.48
6. Step 6: Final answer
   x = 59,806.48