Finding the Fourth Proportional to 21,222.12, 29,287.32 and 12,725.63

Step by Step Solution

1. Step 1: Write the proportion equation
   21,222.12 : 29,287.32 = 12,725.63 : x
2. Step 2: Convert to fraction form
   21,222.12/29,287.32 = 12,725.63/x
3. Step 3: Cross multiply
   21,222.12x = 29,287.32 × 12,725.63
4. Step 4: Simplify right side
   21,222.12x = 372,699,387.95
5. Step 5: Solve for x
   x = 372,699,387.95/21,222.12
6. Step 6: Final answer
   x = 17,561.84