Finding the Fourth Proportional to 21,085.93, 29,097.77 and 12,136.31

Step by Step Solution

1. Step 1: Write the proportion equation
   21,085.93 : 29,097.77 = 12,136.31 : x
2. Step 2: Convert to fraction form
   21,085.93/29,097.77 = 12,136.31/x
3. Step 3: Cross multiply
   21,085.93x = 29,097.77 × 12,136.31
4. Step 4: Simplify right side
   21,085.93x = 353,139,557.03
5. Step 5: Solve for x
   x = 353,139,557.03/21,085.93
6. Step 6: Final answer
   x = 16,747.64