Finding the Fourth Proportional to 21,579.89, 29,779.89 and 12,019.52

Step by Step Solution

1. Step 1: Write the proportion equation
   21,579.89 : 29,779.89 = 12,019.52 : x
2. Step 2: Convert to fraction form
   21,579.89/29,779.89 = 12,019.52/x
3. Step 3: Cross multiply
   21,579.89x = 29,779.89 × 12,019.52
4. Step 4: Simplify right side
   21,579.89x = 357,939,834.55
5. Step 5: Solve for x
   x = 357,939,834.55/21,579.89
6. Step 6: Final answer
   x = 16,586.74