Finding the Fourth Proportional to 9,278.78, 12,804.90 and 5,245.81

Step by Step Solution

1. Step 1: Write the proportion equation
   9,278.78 : 12,804.90 = 5,245.81 : x
2. Step 2: Convert to fraction form
   9,278.78/12,804.90 = 5,245.81/x
3. Step 3: Cross multiply
   9,278.78x = 12,804.90 × 5,245.81
4. Step 4: Simplify right side
   9,278.78x = 67,172,072.47
5. Step 5: Solve for x
   x = 67,172,072.47/9,278.78
6. Step 6: Final answer
   x = 7,239.32