Finding the Fourth Proportional to 1,355.90, 1,870.96 and 766.32

Step by Step Solution

1. Step 1: Write the proportion equation
   1,355.90 : 1,870.96 = 766.32 : x
2. Step 2: Convert to fraction form
   1,355.90/1,870.96 = 766.32/x
3. Step 3: Cross multiply
   1,355.90x = 1,870.96 × 766.32
4. Step 4: Simplify right side
   1,355.90x = 1,433,754.07
5. Step 5: Solve for x
   x = 1,433,754.07/1,355.90
6. Step 6: Final answer
   x = 1,057.42