Finding the Fourth Proportional to 20,578.42, 30,861.27 and 7,429.09

Step by Step Solution

1. Step 1: Write the proportion equation
   20,578.42 : 30,861.27 = 7,429.09 : x
2. Step 2: Convert to fraction form
   20,578.42/30,861.27 = 7,429.09/x
3. Step 3: Cross multiply
   20,578.42x = 30,861.27 × 7,429.09
4. Step 4: Simplify right side
   20,578.42x = 229,271,152.34
5. Step 5: Solve for x
   x = 229,271,152.34/20,578.42
6. Step 6: Final answer
   x = 11,141.34