Finding the Fourth Proportional to 19,411.39, 29,116.85 and 13,688.78

Step by Step Solution

1. Step 1: Write the proportion equation
   19,411.39 : 29,116.85 = 13,688.78 : x
2. Step 2: Convert to fraction form
   19,411.39/29,116.85 = 13,688.78/x
3. Step 3: Cross multiply
   19,411.39x = 29,116.85 × 13,688.78
4. Step 4: Simplify right side
   19,411.39x = 398,574,153.94
5. Step 5: Solve for x
   x = 398,574,153.94/19,411.39
6. Step 6: Final answer
   x = 20,533.00