Finding the Fourth Proportional to 1,338.38, 2,007.56 and 413.69

Step by Step Solution

1. Step 1: Write the proportion equation
   1,338.38 : 2,007.56 = 413.69 : x
2. Step 2: Convert to fraction form
   1,338.38/2,007.56 = 413.69/x
3. Step 3: Cross multiply
   1,338.38x = 2,007.56 × 413.69
4. Step 4: Simplify right side
   1,338.38x = 830,507.50
5. Step 5: Solve for x
   x = 830,507.50/1,338.38
6. Step 6: Final answer
   x = 620.53