Finding the Third Proportional to 345.94 and 646.31

Step by Step Solution

1. Step 1: Write the proportion equation
   345.94 : 646.31 = 646.31 : x
2. Step 2: Convert to fraction form
   345.94/646.31 = 646.31/x
3. Step 3: Cross multiply
   345.94x = 646.31 × 646.31
4. Step 4: Simplify right side
   345.94x = 417,719.85
5. Step 5: Solve for x
   x = 417,719.85/345.94
6. Step 6: Final answer
   x = 1,207.50