Finding the Fourth Proportional to 1,356.24, 1,871.52 and 766.80

Step by Step Solution

1. Step 1: Write the proportion equation
   1,356.24 : 1,871.52 = 766.80 : x
2. Step 2: Convert to fraction form
   1,356.24/1,871.52 = 766.80/x
3. Step 3: Cross multiply
   1,356.24x = 1,871.52 × 766.80
4. Step 4: Simplify right side
   1,356.24x = 1,435,081.54
5. Step 5: Solve for x
   x = 1,435,081.54/1,356.24
6. Step 6: Final answer
   x = 1,058.13