Finding the Fourth Proportional to 21,042.69, 29,041.47 and 12,090.15

Step by Step Solution

1. Step 1: Write the proportion equation
   21,042.69 : 29,041.47 = 12,090.15 : x
2. Step 2: Convert to fraction form
   21,042.69/29,041.47 = 12,090.15/x
3. Step 3: Cross multiply
   21,042.69x = 29,041.47 × 12,090.15
4. Step 4: Simplify right side
   21,042.69x = 351,115,728.52
5. Step 5: Solve for x
   x = 351,115,728.52/21,042.69
6. Step 6: Final answer
   x = 16,685.88