Finding the Fourth Proportional to 9,761.31, 13,469.09 and 5,781.78

Step by Step Solution

1. Step 1: Write the proportion equation
   9,761.31 : 13,469.09 = 5,781.78 : x
2. Step 2: Convert to fraction form
   9,761.31/13,469.09 = 5,781.78/x
3. Step 3: Cross multiply
   9,761.31x = 13,469.09 × 5,781.78
4. Step 4: Simplify right side
   9,761.31x = 77,875,286.27
5. Step 5: Solve for x
   x = 77,875,286.27/9,761.31
6. Step 6: Final answer
   x = 7,977.95