Finding the Fourth Proportional to 21,561.30, 29,753.82 and 12,000.87

Step by Step Solution

1. Step 1: Write the proportion equation
   21,561.30 : 29,753.82 = 12,000.87 : x
2. Step 2: Convert to fraction form
   21,561.30/29,753.82 = 12,000.87/x
3. Step 3: Cross multiply
   21,561.30x = 29,753.82 × 12,000.87
4. Step 4: Simplify right side
   21,561.30x = 357,071,725.82
5. Step 5: Solve for x
   x = 357,071,725.82/21,561.30
6. Step 6: Final answer
   x = 16,560.77