Finding the Fourth Proportional to 20,342.30, 28,076.72 and 12,387.06

Step by Step Solution

1. Step 1: Write the proportion equation
   20,342.30 : 28,076.72 = 12,387.06 : x
2. Step 2: Convert to fraction form
   20,342.30/28,076.72 = 12,387.06/x
3. Step 3: Cross multiply
   20,342.30x = 28,076.72 × 12,387.06
4. Step 4: Simplify right side
   20,342.30x = 347,787,953.31
5. Step 5: Solve for x
   x = 347,787,953.31/20,342.30
6. Step 6: Final answer
   x = 17,096.79