Finding the Fourth Proportional to 12,909.29, 19,359.61 and 4,142.12

Step by Step Solution

1. Step 1: Write the proportion equation
   12,909.29 : 19,359.61 = 4,142.12 : x
2. Step 2: Convert to fraction form
   12,909.29/19,359.61 = 4,142.12/x
3. Step 3: Cross multiply
   12,909.29x = 19,359.61 × 4,142.12
4. Step 4: Simplify right side
   12,909.29x = 80,189,827.77
5. Step 5: Solve for x
   x = 80,189,827.77/12,909.29
6. Step 6: Final answer
   x = 6,211.79