Finding the Fourth Proportional to 9,404.51, 12,978.36 and 5,155.49

Step by Step Solution

1. Step 1: Write the proportion equation
   9,404.51 : 12,978.36 = 5,155.49 : x
2. Step 2: Convert to fraction form
   9,404.51/12,978.36 = 5,155.49/x
3. Step 3: Cross multiply
   9,404.51x = 12,978.36 × 5,155.49
4. Step 4: Simplify right side
   9,404.51x = 66,909,714.53
5. Step 5: Solve for x
   x = 66,909,714.53/9,404.51
6. Step 6: Final answer
   x = 7,114.64