Finding the Third Proportional to 427.03 and 640.59

Step by Step Solution

1. Step 1: Write the proportion equation
   427.03 : 640.59 = 640.59 : x
2. Step 2: Convert to fraction form
   427.03/640.59 = 640.59/x
3. Step 3: Cross multiply
   427.03x = 640.59 × 640.59
4. Step 4: Simplify right side
   427.03x = 410,360.35
5. Step 5: Solve for x
   x = 410,360.35/427.03
6. Step 6: Final answer
   x = 960.96