Finding the Fourth Proportional to 5,156.96, 7,721.55 and 4,243.55

Step by Step Solution

1. Step 1: Write the proportion equation
   5,156.96 : 7,721.55 = 4,243.55 : x
2. Step 2: Convert to fraction form
   5,156.96/7,721.55 = 4,243.55/x
3. Step 3: Cross multiply
   5,156.96x = 7,721.55 × 4,243.55
4. Step 4: Simplify right side
   5,156.96x = 32,766,744.89
5. Step 5: Solve for x
   x = 32,766,744.89/5,156.96
6. Step 6: Final answer
   x = 6,353.89