Finding the Fourth Proportional to 10,713.96, 14,789.15 and 8,721.06

Step by Step Solution

1. Step 1: Write the proportion equation
   10,713.96 : 14,789.15 = 8,721.06 : x
2. Step 2: Convert to fraction form
   10,713.96/14,789.15 = 8,721.06/x
3. Step 3: Cross multiply
   10,713.96x = 14,789.15 × 8,721.06
4. Step 4: Simplify right side
   10,713.96x = 128,977,064.50
5. Step 5: Solve for x
   x = 128,977,064.50/10,713.96
6. Step 6: Final answer
   x = 12,038.23