Finding the Fourth Proportional to 13,665.81, 18,858.73 and 7,699.40

Step by Step Solution

1. Step 1: Write the proportion equation
   13,665.81 : 18,858.73 = 7,699.40 : x
2. Step 2: Convert to fraction form
   13,665.81/18,858.73 = 7,699.40/x
3. Step 3: Cross multiply
   13,665.81x = 18,858.73 × 7,699.40
4. Step 4: Simplify right side
   13,665.81x = 145,200,792.22
5. Step 5: Solve for x
   x = 145,200,792.22/13,665.81
6. Step 6: Final answer
   x = 10,625.12