Finding the Fourth Proportional to 1,131.38, 1,697.27 and 390.96

Step by Step Solution

1. Step 1: Write the proportion equation
   1,131.38 : 1,697.27 = 390.96 : x
2. Step 2: Convert to fraction form
   1,131.38/1,697.27 = 390.96/x
3. Step 3: Cross multiply
   1,131.38x = 1,697.27 × 390.96
4. Step 4: Simplify right side
   1,131.38x = 663,562.72
5. Step 5: Solve for x
   x = 663,562.72/1,131.38
6. Step 6: Final answer
   x = 586.51