Finding the Fourth Proportional to 21,265.59, 31,879.89 and 8,777.82

Step by Step Solution

1. Step 1: Write the proportion equation
   21,265.59 : 31,879.89 = 8,777.82 : x
2. Step 2: Convert to fraction form
   21,265.59/31,879.89 = 8,777.82/x
3. Step 3: Cross multiply
   21,265.59x = 31,879.89 × 8,777.82
4. Step 4: Simplify right side
   21,265.59x = 279,835,936.04
5. Step 5: Solve for x
   x = 279,835,936.04/21,265.59
6. Step 6: Final answer
   x = 13,159.10