Finding the Fourth Proportional to 1,355.48, 1,870.40 and 765.92

Step by Step Solution

1. Step 1: Write the proportion equation
   1,355.48 : 1,870.40 = 765.92 : x
2. Step 2: Convert to fraction form
   1,355.48/1,870.40 = 765.92/x
3. Step 3: Cross multiply
   1,355.48x = 1,870.40 × 765.92
4. Step 4: Simplify right side
   1,355.48x = 1,432,576.77
5. Step 5: Solve for x
   x = 1,432,576.77/1,355.48
6. Step 6: Final answer
   x = 1,056.88