Finding the Third Proportional to 426.38 and 680.25

Step by Step Solution

1. Step 1: Write the proportion equation
   426.38 : 680.25 = 680.25 : x
2. Step 2: Convert to fraction form
   426.38/680.25 = 680.25/x
3. Step 3: Cross multiply
   426.38x = 680.25 × 680.25
4. Step 4: Simplify right side
   426.38x = 462,740.06
5. Step 5: Solve for x
   x = 462,740.06/426.38
6. Step 6: Final answer
   x = 1,085.29