Finding the Fourth Proportional to 1,355.34, 1,870.37 and 765.87

Step by Step Solution

1. Step 1: Write the proportion equation
   1,355.34 : 1,870.37 = 765.87 : x
2. Step 2: Convert to fraction form
   1,355.34/1,870.37 = 765.87/x
3. Step 3: Cross multiply
   1,355.34x = 1,870.37 × 765.87
4. Step 4: Simplify right side
   1,355.34x = 1,432,456.44
5. Step 5: Solve for x
   x = 1,432,456.44/1,355.34
6. Step 6: Final answer
   x = 1,056.90