Finding the Fourth Proportional to 15,123.43, 20,867.34 and 9,155.65

Step by Step Solution

1. Step 1: Write the proportion equation
   15,123.43 : 20,867.34 = 9,155.65 : x
2. Step 2: Convert to fraction form
   15,123.43/20,867.34 = 9,155.65/x
3. Step 3: Cross multiply
   15,123.43x = 20,867.34 × 9,155.65
4. Step 4: Simplify right side
   15,123.43x = 191,054,031.26
5. Step 5: Solve for x
   x = 191,054,031.26/15,123.43
6. Step 6: Final answer
   x = 12,632.99