Finding the Fourth Proportional to 39,223.41, 54,128.72 and 21,318.42

Step by Step Solution

1. Step 1: Write the proportion equation
   39,223.41 : 54,128.72 = 21,318.42 : x
2. Step 2: Convert to fraction form
   39,223.41/54,128.72 = 21,318.42/x
3. Step 3: Cross multiply
   39,223.41x = 54,128.72 × 21,318.42
4. Step 4: Simplify right side
   39,223.41x = 1,153,938,787.02
5. Step 5: Solve for x
   x = 1,153,938,787.02/39,223.41
6. Step 6: Final answer
   x = 29,419.64