Finding the Fourth Proportional to 21,312.72, 29,426.09 and 13,777.29

Step by Step Solution

1. Step 1: Write the proportion equation
   21,312.72 : 29,426.09 = 13,777.29 : x
2. Step 2: Convert to fraction form
   21,312.72/29,426.09 = 13,777.29/x
3. Step 3: Cross multiply
   21,312.72x = 29,426.09 × 13,777.29
4. Step 4: Simplify right side
   21,312.72x = 405,411,706.61
5. Step 5: Solve for x
   x = 405,411,706.61/21,312.72
6. Step 6: Final answer
   x = 19,022.05