Finding the Third Proportional to 639.14 and 1,342.83

Step by Step Solution

1. Step 1: Write the proportion equation
   639.14 : 1,342.83 = 1,342.83 : x
2. Step 2: Convert to fraction form
   639.14/1,342.83 = 1,342.83/x
3. Step 3: Cross multiply
   639.14x = 1,342.83 × 1,342.83
4. Step 4: Simplify right side
   639.14x = 1,803,187.37
5. Step 5: Solve for x
   x = 1,803,187.37/639.14
6. Step 6: Final answer
   x = 2,821.27