Finding the Fourth Proportional to 1,151.91, 1,590.17 and 857.61

Step by Step Solution

1. Step 1: Write the proportion equation
   1,151.91 : 1,590.17 = 857.61 : x
2. Step 2: Convert to fraction form
   1,151.91/1,590.17 = 857.61/x
3. Step 3: Cross multiply
   1,151.91x = 1,590.17 × 857.61
4. Step 4: Simplify right side
   1,151.91x = 1,363,741.41
5. Step 5: Solve for x
   x = 1,363,741.41/1,151.91
6. Step 6: Final answer
   x = 1,183.90