Finding the Fourth Proportional to 9,429.78, 13,012.74 and 5,238.30

Step by Step Solution

1. Step 1: Write the proportion equation
   9,429.78 : 13,012.74 = 5,238.30 : x
2. Step 2: Convert to fraction form
   9,429.78/13,012.74 = 5,238.30/x
3. Step 3: Cross multiply
   9,429.78x = 13,012.74 × 5,238.30
4. Step 4: Simplify right side
   9,429.78x = 68,164,635.94
5. Step 5: Solve for x
   x = 68,164,635.94/9,429.78
6. Step 6: Final answer
   x = 7,228.66