Finding the Fourth Proportional to 1,388.56, 2,082.46 and 414.43

Step by Step Solution

1. Step 1: Write the proportion equation
   1,388.56 : 2,082.46 = 414.43 : x
2. Step 2: Convert to fraction form
   1,388.56/2,082.46 = 414.43/x
3. Step 3: Cross multiply
   1,388.56x = 2,082.46 × 414.43
4. Step 4: Simplify right side
   1,388.56x = 863,031.83
5. Step 5: Solve for x
   x = 863,031.83/1,388.56
6. Step 6: Final answer
   x = 621.53