Finding the Fourth Proportional to 1,355.66, 1,870.59 and 766.11

Step by Step Solution

1. Step 1: Write the proportion equation
   1,355.66 : 1,870.59 = 766.11 : x
2. Step 2: Convert to fraction form
   1,355.66/1,870.59 = 766.11/x
3. Step 3: Cross multiply
   1,355.66x = 1,870.59 × 766.11
4. Step 4: Simplify right side
   1,355.66x = 1,433,077.70
5. Step 5: Solve for x
   x = 1,433,077.70/1,355.66
6. Step 6: Final answer
   x = 1,057.11