Finding the Fourth Proportional to 10,081.30, 14,128.40 and 10,081.30

Step by Step Solution

1. Step 1: Write the proportion equation
   10,081.30 : 14,128.40 = 10,081.30 : x
2. Step 2: Convert to fraction form
   10,081.30/14,128.40 = 10,081.30/x
3. Step 3: Cross multiply
   10,081.30x = 14,128.40 × 10,081.30
4. Step 4: Simplify right side
   10,081.30x = 142,432,638.92
5. Step 5: Solve for x
   x = 142,432,638.92/10,081.30
6. Step 6: Final answer
   x = 14,128.40