Finding the Fourth Proportional to 1,105.97, 1,659.78 and 413.06

Step by Step Solution

1. Step 1: Write the proportion equation
   1,105.97 : 1,659.78 = 413.06 : x
2. Step 2: Convert to fraction form
   1,105.97/1,659.78 = 413.06/x
3. Step 3: Cross multiply
   1,105.97x = 1,659.78 × 413.06
4. Step 4: Simplify right side
   1,105.97x = 685,580.43
5. Step 5: Solve for x
   x = 685,580.43/1,105.97
6. Step 6: Final answer
   x = 619.89