Finding the Fourth Proportional to 1,356.21, 1,871.61 and 766.83

Step by Step Solution

1. Step 1: Write the proportion equation
   1,356.21 : 1,871.61 = 766.83 : x
2. Step 2: Convert to fraction form
   1,356.21/1,871.61 = 766.83/x
3. Step 3: Cross multiply
   1,356.21x = 1,871.61 × 766.83
4. Step 4: Simplify right side
   1,356.21x = 1,435,210.84
5. Step 5: Solve for x
   x = 1,435,210.84/1,356.21
6. Step 6: Final answer
   x = 1,058.25