Finding the Fourth Proportional to 9,156.65, 12,636.96 and 5,178.47

Step by Step Solution

1. Step 1: Write the proportion equation
   9,156.65 : 12,636.96 = 5,178.47 : x
2. Step 2: Convert to fraction form
   9,156.65/12,636.96 = 5,178.47/x
3. Step 3: Cross multiply
   9,156.65x = 12,636.96 × 5,178.47
4. Step 4: Simplify right side
   9,156.65x = 65,440,118.25
5. Step 5: Solve for x
   x = 65,440,118.25/9,156.65
6. Step 6: Final answer
   x = 7,146.73