Finding the Fourth Proportional to 9,156.54, 12,636.28 and 5,178.25

Step by Step Solution

1. Step 1: Write the proportion equation
   9,156.54 : 12,636.28 = 5,178.25 : x
2. Step 2: Convert to fraction form
   9,156.54/12,636.28 = 5,178.25/x
3. Step 3: Cross multiply
   9,156.54x = 12,636.28 × 5,178.25
4. Step 4: Simplify right side
   9,156.54x = 65,433,816.91
5. Step 5: Solve for x
   x = 65,433,816.91/9,156.54
6. Step 6: Final answer
   x = 7,146.13