Finding the Fourth Proportional to 3,320.55, 4,978.26 and 2,151.72

Step by Step Solution

1. Step 1: Write the proportion equation
   3,320.55 : 4,978.26 = 2,151.72 : x
2. Step 2: Convert to fraction form
   3,320.55/4,978.26 = 2,151.72/x
3. Step 3: Cross multiply
   3,320.55x = 4,978.26 × 2,151.72
4. Step 4: Simplify right side
   3,320.55x = 10,711,821.61
5. Step 5: Solve for x
   x = 10,711,821.61/3,320.55
6. Step 6: Final answer
   x = 3,225.92