Finding the Fourth Proportional to 9,665.16, 13,337.70 and 5,685.40

Step by Step Solution

1. Step 1: Write the proportion equation
   9,665.16 : 13,337.70 = 5,685.40 : x
2. Step 2: Convert to fraction form
   9,665.16/13,337.70 = 5,685.40/x
3. Step 3: Cross multiply
   9,665.16x = 13,337.70 × 5,685.40
4. Step 4: Simplify right side
   9,665.16x = 75,830,159.58
5. Step 5: Solve for x
   x = 75,830,159.58/9,665.16
6. Step 6: Final answer
   x = 7,845.72