Finding the Fourth Proportional to 21,040.86, 29,042.55 and 13,079.10

Step by Step Solution

1. Step 1: Write the proportion equation
   21,040.86 : 29,042.55 = 13,079.10 : x
2. Step 2: Convert to fraction form
   21,040.86/29,042.55 = 13,079.10/x
3. Step 3: Cross multiply
   21,040.86x = 29,042.55 × 13,079.10
4. Step 4: Simplify right side
   21,040.86x = 379,850,415.71
5. Step 5: Solve for x
   x = 379,850,415.71/21,040.86
6. Step 6: Final answer
   x = 18,052.99