Finding the Third Proportional to 685.34 and 1,490.27

Step by Step Solution

1. Step 1: Write the proportion equation
   685.34 : 1,490.27 = 1,490.27 : x
2. Step 2: Convert to fraction form
   685.34/1,490.27 = 1,490.27/x
3. Step 3: Cross multiply
   685.34x = 1,490.27 × 1,490.27
4. Step 4: Simplify right side
   685.34x = 2,220,914.92
5. Step 5: Solve for x
   x = 2,220,914.92/685.34
6. Step 6: Final answer
   x = 3,240.62