Finding the Fourth Proportional to 7,109.31, 9,811.16 and 3,965.50

Step by Step Solution

1. Step 1: Write the proportion equation
   7,109.31 : 9,811.16 = 3,965.50 : x
2. Step 2: Convert to fraction form
   7,109.31/9,811.16 = 3,965.50/x
3. Step 3: Cross multiply
   7,109.31x = 9,811.16 × 3,965.50
4. Step 4: Simplify right side
   7,109.31x = 38,906,154.98
5. Step 5: Solve for x
   x = 38,906,154.98/7,109.31
6. Step 6: Final answer
   x = 5,472.56