Finding the Fourth Proportional to 1,285.89, 1,774.55 and 755.15

Step by Step Solution

1. Step 1: Write the proportion equation
   1,285.89 : 1,774.55 = 755.15 : x
2. Step 2: Convert to fraction form
   1,285.89/1,774.55 = 755.15/x
3. Step 3: Cross multiply
   1,285.89x = 1,774.55 × 755.15
4. Step 4: Simplify right side
   1,285.89x = 1,340,051.43
5. Step 5: Solve for x
   x = 1,340,051.43/1,285.89
6. Step 6: Final answer
   x = 1,042.12