Finding the Fourth Proportional to 10,978.76, 16,470.15 and 4,405.60

Step by Step Solution

1. Step 1: Write the proportion equation
   10,978.76 : 16,470.15 = 4,405.60 : x
2. Step 2: Convert to fraction form
   10,978.76/16,470.15 = 4,405.60/x
3. Step 3: Cross multiply
   10,978.76x = 16,470.15 × 4,405.60
4. Step 4: Simplify right side
   10,978.76x = 72,560,892.84
5. Step 5: Solve for x
   x = 72,560,892.84/10,978.76
6. Step 6: Final answer
   x = 6,609.21