Finding the Fourth Proportional to 1,356.85, 1,872.20 and 825.59

Step by Step Solution

1. Step 1: Write the proportion equation
   1,356.85 : 1,872.20 = 825.59 : x
2. Step 2: Convert to fraction form
   1,356.85/1,872.20 = 825.59/x
3. Step 3: Cross multiply
   1,356.85x = 1,872.20 × 825.59
4. Step 4: Simplify right side
   1,356.85x = 1,545,656.11
5. Step 5: Solve for x
   x = 1,545,656.11/1,356.85
6. Step 6: Final answer
   x = 1,139.15