Finding the Fourth Proportional to 1,490.57, 2,057.46 and 869.69

Step by Step Solution

1. Step 1: Write the proportion equation
   1,490.57 : 2,057.46 = 869.69 : x
2. Step 2: Convert to fraction form
   1,490.57/2,057.46 = 869.69/x
3. Step 3: Cross multiply
   1,490.57x = 2,057.46 × 869.69
4. Step 4: Simplify right side
   1,490.57x = 1,789,352.39
5. Step 5: Solve for x
   x = 1,789,352.39/1,490.57
6. Step 6: Final answer
   x = 1,200.45