Finding the Fourth Proportional to 9,388.90, 12,957.84 and 5,356.72

Step by Step Solution

1. Step 1: Write the proportion equation
   9,388.90 : 12,957.84 = 5,356.72 : x
2. Step 2: Convert to fraction form
   9,388.90/12,957.84 = 5,356.72/x
3. Step 3: Cross multiply
   9,388.90x = 12,957.84 × 5,356.72
4. Step 4: Simplify right side
   9,388.90x = 69,411,520.68
5. Step 5: Solve for x
   x = 69,411,520.68/9,388.90
6. Step 6: Final answer
   x = 7,392.93