Finding the Fourth Proportional to 10,242.61, 15,284.03 and 9,139.39

Step by Step Solution

1. Step 1: Write the proportion equation
   10,242.61 : 15,284.03 = 9,139.39 : x
2. Step 2: Convert to fraction form
   10,242.61/15,284.03 = 9,139.39/x
3. Step 3: Cross multiply
   10,242.61x = 15,284.03 × 9,139.39
4. Step 4: Simplify right side
   10,242.61x = 139,686,710.94
5. Step 5: Solve for x
   x = 139,686,710.94/10,242.61
6. Step 6: Final answer
   x = 13,637.80