Finding the Fourth Proportional to 1,355.70, 1,870.86 and 766.24

Step by Step Solution

1. Step 1: Write the proportion equation
   1,355.70 : 1,870.86 = 766.24 : x
2. Step 2: Convert to fraction form
   1,355.70/1,870.86 = 766.24/x
3. Step 3: Cross multiply
   1,355.70x = 1,870.86 × 766.24
4. Step 4: Simplify right side
   1,355.70x = 1,433,527.77
5. Step 5: Solve for x
   x = 1,433,527.77/1,355.70
6. Step 6: Final answer
   x = 1,057.41