Finding the Fourth Proportional to 21,610.29, 29,817.69 and 13,116.87

Step by Step Solution

1. Step 1: Write the proportion equation
   21,610.29 : 29,817.69 = 13,116.87 : x
2. Step 2: Convert to fraction form
   21,610.29/29,817.69 = 13,116.87/x
3. Step 3: Cross multiply
   21,610.29x = 29,817.69 × 13,116.87
4. Step 4: Simplify right side
   21,610.29x = 391,114,950.71
5. Step 5: Solve for x
   x = 391,114,950.71/21,610.29
6. Step 6: Final answer
   x = 18,098.55