Finding the Fourth Proportional to 1,208.39, 1,667.88 and 684.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,208.39 : 1,667.88 = 684.72 : x
2. Step 2: Convert to fraction form
   1,208.39/1,667.88 = 684.72/x
3. Step 3: Cross multiply
   1,208.39x = 1,667.88 × 684.72
4. Step 4: Simplify right side
   1,208.39x = 1,142,030.79
5. Step 5: Solve for x
   x = 1,142,030.79/1,208.39
6. Step 6: Final answer
   x = 945.09