Finding the Fourth Proportional to 21,481.61, 29,637.50 and 12,986.33

Step by Step Solution

1. Step 1: Write the proportion equation
   21,481.61 : 29,637.50 = 12,986.33 : x
2. Step 2: Convert to fraction form
   21,481.61/29,637.50 = 12,986.33/x
3. Step 3: Cross multiply
   21,481.61x = 29,637.50 × 12,986.33
4. Step 4: Simplify right side
   21,481.61x = 384,882,142.26
5. Step 5: Solve for x
   x = 384,882,142.26/21,481.61
6. Step 6: Final answer
   x = 17,916.82