Finding the Fourth Proportional to 1,355.50, 1,870.44 and 765.91

Step by Step Solution

1. Step 1: Write the proportion equation
   1,355.50 : 1,870.44 = 765.91 : x
2. Step 2: Convert to fraction form
   1,355.50/1,870.44 = 765.91/x
3. Step 3: Cross multiply
   1,355.50x = 1,870.44 × 765.91
4. Step 4: Simplify right side
   1,355.50x = 1,432,588.70
5. Step 5: Solve for x
   x = 1,432,588.70/1,355.50
6. Step 6: Final answer
   x = 1,056.87