Finding the Fourth Proportional to 21,223.72, 29,280.18 and 12,825.64

Step by Step Solution

1. Step 1: Write the proportion equation
   21,223.72 : 29,280.18 = 12,825.64 : x
2. Step 2: Convert to fraction form
   21,223.72/29,280.18 = 12,825.64/x
3. Step 3: Cross multiply
   21,223.72x = 29,280.18 × 12,825.64
4. Step 4: Simplify right side
   21,223.72x = 375,537,047.82
5. Step 5: Solve for x
   x = 375,537,047.82/21,223.72
6. Step 6: Final answer
   x = 17,694.21