Finding the Fourth Proportional to 21,609.72, 29,824.20 and 12,181.32

Step by Step Solution

1. Step 1: Write the proportion equation
   21,609.72 : 29,824.20 = 12,181.32 : x
2. Step 2: Convert to fraction form
   21,609.72/29,824.20 = 12,181.32/x
3. Step 3: Cross multiply
   21,609.72x = 29,824.20 × 12,181.32
4. Step 4: Simplify right side
   21,609.72x = 363,298,123.94
5. Step 5: Solve for x
   x = 363,298,123.94/21,609.72
6. Step 6: Final answer
   x = 16,811.79