Finding the Fourth Proportional to 5,100.62, 7,642.20 and 3,989.61

Step by Step Solution

1. Step 1: Write the proportion equation
   5,100.62 : 7,642.20 = 3,989.61 : x
2. Step 2: Convert to fraction form
   5,100.62/7,642.20 = 3,989.61/x
3. Step 3: Cross multiply
   5,100.62x = 7,642.20 × 3,989.61
4. Step 4: Simplify right side
   5,100.62x = 30,489,397.54
5. Step 5: Solve for x
   x = 30,489,397.54/5,100.62
6. Step 6: Final answer
   x = 5,977.59