Finding the Fourth Proportional to 20,925.34, 28,870.02 and 12,430.06

Step by Step Solution

1. Step 1: Write the proportion equation
   20,925.34 : 28,870.02 = 12,430.06 : x
2. Step 2: Convert to fraction form
   20,925.34/28,870.02 = 12,430.06/x
3. Step 3: Cross multiply
   20,925.34x = 28,870.02 × 12,430.06
4. Step 4: Simplify right side
   20,925.34x = 358,856,080.80
5. Step 5: Solve for x
   x = 358,856,080.80/20,925.34
6. Step 6: Final answer
   x = 17,149.35