Finding the Fourth Proportional to 1,208.47, 1,667.39 and 766.21

Step by Step Solution

1. Step 1: Write the proportion equation
   1,208.47 : 1,667.39 = 766.21 : x
2. Step 2: Convert to fraction form
   1,208.47/1,667.39 = 766.21/x
3. Step 3: Cross multiply
   1,208.47x = 1,667.39 × 766.21
4. Step 4: Simplify right side
   1,208.47x = 1,277,562.89
5. Step 5: Solve for x
   x = 1,277,562.89/1,208.47
6. Step 6: Final answer
   x = 1,057.18