Finding the Fourth Proportional to 12,388.69, 17,099.43 and 7,609.78

Step by Step Solution

1. Step 1: Write the proportion equation
   12,388.69 : 17,099.43 = 7,609.78 : x
2. Step 2: Convert to fraction form
   12,388.69/17,099.43 = 7,609.78/x
3. Step 3: Cross multiply
   12,388.69x = 17,099.43 × 7,609.78
4. Step 4: Simplify right side
   12,388.69x = 130,122,900.43
5. Step 5: Solve for x
   x = 130,122,900.43/12,388.69
6. Step 6: Final answer
   x = 10,503.36