Finding the Fourth Proportional to 10,429.38, 15,644.12 and 2,638.20

Step by Step Solution

1. Step 1: Write the proportion equation
   10,429.38 : 15,644.12 = 2,638.20 : x
2. Step 2: Convert to fraction form
   10,429.38/15,644.12 = 2,638.20/x
3. Step 3: Cross multiply
   10,429.38x = 15,644.12 × 2,638.20
4. Step 4: Simplify right side
   10,429.38x = 41,272,317.38
5. Step 5: Solve for x
   x = 41,272,317.38/10,429.38
6. Step 6: Final answer
   x = 3,957.31