Finding the Fourth Proportional to 21,331.27, 29,429.89 and 12,946.15

Step by Step Solution

1. Step 1: Write the proportion equation
   21,331.27 : 29,429.89 = 12,946.15 : x
2. Step 2: Convert to fraction form
   21,331.27/29,429.89 = 12,946.15/x
3. Step 3: Cross multiply
   21,331.27x = 29,429.89 × 12,946.15
4. Step 4: Simplify right side
   21,331.27x = 381,003,770.42
5. Step 5: Solve for x
   x = 381,003,770.42/21,331.27
6. Step 6: Final answer
   x = 17,861.28