Finding the Fourth Proportional to 9,940.40, 14,905.76 and 5,781.60

Step by Step Solution

1. Step 1: Write the proportion equation
   9,940.40 : 14,905.76 = 5,781.60 : x
2. Step 2: Convert to fraction form
   9,940.40/14,905.76 = 5,781.60/x
3. Step 3: Cross multiply
   9,940.40x = 14,905.76 × 5,781.60
4. Step 4: Simplify right side
   9,940.40x = 86,179,142.02
5. Step 5: Solve for x
   x = 86,179,142.02/9,940.40
6. Step 6: Final answer
   x = 8,669.58