Finding the Fourth Proportional to 21,066.38, 31,591.82 and 8,579.63

Step by Step Solution

1. Step 1: Write the proportion equation
   21,066.38 : 31,591.82 = 8,579.63 : x
2. Step 2: Convert to fraction form
   21,066.38/31,591.82 = 8,579.63/x
3. Step 3: Cross multiply
   21,066.38x = 31,591.82 × 8,579.63
4. Step 4: Simplify right side
   21,066.38x = 271,045,925.77
5. Step 5: Solve for x
   x = 271,045,925.77/21,066.38
6. Step 6: Final answer
   x = 12,866.28