Finding the Fourth Proportional to 10,978.20, 16,472.70 and 5,133.78

Step by Step Solution

1. Step 1: Write the proportion equation
   10,978.20 : 16,472.70 = 5,133.78 : x
2. Step 2: Convert to fraction form
   10,978.20/16,472.70 = 5,133.78/x
3. Step 3: Cross multiply
   10,978.20x = 16,472.70 × 5,133.78
4. Step 4: Simplify right side
   10,978.20x = 84,567,217.81
5. Step 5: Solve for x
   x = 84,567,217.81/10,978.20
6. Step 6: Final answer
   x = 7,703.20