Finding the Fourth Proportional to 1,338.56, 2,007.86 and 414.10

Step by Step Solution

1. Step 1: Write the proportion equation
   1,338.56 : 2,007.86 = 414.10 : x
2. Step 2: Convert to fraction form
   1,338.56/2,007.86 = 414.10/x
3. Step 3: Cross multiply
   1,338.56x = 2,007.86 × 414.10
4. Step 4: Simplify right side
   1,338.56x = 831,442.72
5. Step 5: Solve for x
   x = 831,442.72/1,338.56
6. Step 6: Final answer
   x = 621.15