Finding the Fourth Proportional to 768.89, 1,061.04 and 419.57

Step by Step Solution

1. Step 1: Write the proportion equation
   768.89 : 1,061.04 = 419.57 : x
2. Step 2: Convert to fraction form
   768.89/1,061.04 = 419.57/x
3. Step 3: Cross multiply
   768.89x = 1,061.04 × 419.57
4. Step 4: Simplify right side
   768.89x = 445,180.55
5. Step 5: Solve for x
   x = 445,180.55/768.89
6. Step 6: Final answer
   x = 578.99