Finding the Fourth Proportional to 6,419.89, 9,623.14 and 3,128.46

Step by Step Solution

1. Step 1: Write the proportion equation
   6,419.89 : 9,623.14 = 3,128.46 : x
2. Step 2: Convert to fraction form
   6,419.89/9,623.14 = 3,128.46/x
3. Step 3: Cross multiply
   6,419.89x = 9,623.14 × 3,128.46
4. Step 4: Simplify right side
   6,419.89x = 30,105,608.56
5. Step 5: Solve for x
   x = 30,105,608.56/6,419.89
6. Step 6: Final answer
   x = 4,689.43