Finding the Fourth Proportional to 21,196.56, 29,251.36 and 13,243.40

Step by Step Solution

1. Step 1: Write the proportion equation
   21,196.56 : 29,251.36 = 13,243.40 : x
2. Step 2: Convert to fraction form
   21,196.56/29,251.36 = 13,243.40/x
3. Step 3: Cross multiply
   21,196.56x = 29,251.36 × 13,243.40
4. Step 4: Simplify right side
   21,196.56x = 387,387,314.77
5. Step 5: Solve for x
   x = 387,387,314.77/21,196.56
6. Step 6: Final answer
   x = 18,275.96