Finding the Fourth Proportional to 1,385.16, 1,911.32 and 825.62

Step by Step Solution

1. Step 1: Write the proportion equation
   1,385.16 : 1,911.32 = 825.62 : x
2. Step 2: Convert to fraction form
   1,385.16/1,911.32 = 825.62/x
3. Step 3: Cross multiply
   1,385.16x = 1,911.32 × 825.62
4. Step 4: Simplify right side
   1,385.16x = 1,578,010.33
5. Step 5: Solve for x
   x = 1,578,010.33/1,385.16
6. Step 6: Final answer
   x = 1,139.23