Finding the Fourth Proportional to 21,429.10, 32,118.81 and 12,671.38

Step by Step Solution

1. Step 1: Write the proportion equation
   21,429.10 : 32,118.81 = 12,671.38 : x
2. Step 2: Convert to fraction form
   21,429.10/32,118.81 = 12,671.38/x
3. Step 3: Cross multiply
   21,429.10x = 32,118.81 × 12,671.38
4. Step 4: Simplify right side
   21,429.10x = 406,989,646.66
5. Step 5: Solve for x
   x = 406,989,646.66/21,429.10
6. Step 6: Final answer
   x = 18,992.38