Finding the Fourth Proportional to 21,142.82, 29,176.71 and 12,190.70

Step by Step Solution

1. Step 1: Write the proportion equation
   21,142.82 : 29,176.71 = 12,190.70 : x
2. Step 2: Convert to fraction form
   21,142.82/29,176.71 = 12,190.70/x
3. Step 3: Cross multiply
   21,142.82x = 29,176.71 × 12,190.70
4. Step 4: Simplify right side
   21,142.82x = 355,684,545.82
5. Step 5: Solve for x
   x = 355,684,545.82/21,142.82
6. Step 6: Final answer
   x = 16,822.95