Finding the Fourth Proportional to 21,178.71, 29,227.82 and 12,797.91

Step by Step Solution

1. Step 1: Write the proportion equation
   21,178.71 : 29,227.82 = 12,797.91 : x
2. Step 2: Convert to fraction form
   21,178.71/29,227.82 = 12,797.91/x
3. Step 3: Cross multiply
   21,178.71x = 29,227.82 × 12,797.91
4. Step 4: Simplify right side
   21,178.71x = 374,055,009.86
5. Step 5: Solve for x
   x = 374,055,009.86/21,178.71
6. Step 6: Final answer
   x = 17,661.84