Finding the Fourth Proportional to 9,385.72, 12,951.40 and 5,406.64

Step by Step Solution

1. Step 1: Write the proportion equation
   9,385.72 : 12,951.40 = 5,406.64 : x
2. Step 2: Convert to fraction form
   9,385.72/12,951.40 = 5,406.64/x
3. Step 3: Cross multiply
   9,385.72x = 12,951.40 × 5,406.64
4. Step 4: Simplify right side
   9,385.72x = 70,023,557.30
5. Step 5: Solve for x
   x = 70,023,557.30/9,385.72
6. Step 6: Final answer
   x = 7,460.65