Finding the Fourth Proportional to 10,389.71, 15,654.69 and 8,581.34

Step by Step Solution

1. Step 1: Write the proportion equation
   10,389.71 : 15,654.69 = 8,581.34 : x
2. Step 2: Convert to fraction form
   10,389.71/15,654.69 = 8,581.34/x
3. Step 3: Cross multiply
   10,389.71x = 15,654.69 × 8,581.34
4. Step 4: Simplify right side
   10,389.71x = 134,338,139.21
5. Step 5: Solve for x
   x = 134,338,139.21/10,389.71
6. Step 6: Final answer
   x = 12,929.93