Finding the Fourth Proportional to 8,957.31, 12,360.78 and 4,978.59

Step by Step Solution

1. Step 1: Write the proportion equation
   8,957.31 : 12,360.78 = 4,978.59 : x
2. Step 2: Convert to fraction form
   8,957.31/12,360.78 = 4,978.59/x
3. Step 3: Cross multiply
   8,957.31x = 12,360.78 × 4,978.59
4. Step 4: Simplify right side
   8,957.31x = 61,539,255.70
5. Step 5: Solve for x
   x = 61,539,255.70/8,957.31
6. Step 6: Final answer
   x = 6,870.28