Finding the Fourth Proportional to 9,050.78, 12,489.56 and 5,274.56

Step by Step Solution

1. Step 1: Write the proportion equation
   9,050.78 : 12,489.56 = 5,274.56 : x
2. Step 2: Convert to fraction form
   9,050.78/12,489.56 = 5,274.56/x
3. Step 3: Cross multiply
   9,050.78x = 12,489.56 × 5,274.56
4. Step 4: Simplify right side
   9,050.78x = 65,876,844.77
5. Step 5: Solve for x
   x = 65,876,844.77/9,050.78
6. Step 6: Final answer
   x = 7,278.59