Finding the Fourth Proportional to 9,903.31, 13,666.56 and 5,711.56

Step by Step Solution

1. Step 1: Write the proportion equation
   9,903.31 : 13,666.56 = 5,711.56 : x
2. Step 2: Convert to fraction form
   9,903.31/13,666.56 = 5,711.56/x
3. Step 3: Cross multiply
   9,903.31x = 13,666.56 × 5,711.56
4. Step 4: Simplify right side
   9,903.31x = 78,057,353.98
5. Step 5: Solve for x
   x = 78,057,353.98/9,903.31
6. Step 6: Final answer
   x = 7,881.95