Finding the Fourth Proportional to 9,144.87, 13,635.36 and 8,978.80

Step by Step Solution

1. Step 1: Write the proportion equation
   9,144.87 : 13,635.36 = 8,978.80 : x
2. Step 2: Convert to fraction form
   9,144.87/13,635.36 = 8,978.80/x
3. Step 3: Cross multiply
   9,144.87x = 13,635.36 × 8,978.80
4. Step 4: Simplify right side
   9,144.87x = 122,429,187.10
5. Step 5: Solve for x
   x = 122,429,187.10/9,144.87
6. Step 6: Final answer
   x = 13,387.74