Finding the Third Proportional to 407.50 and 631.31

Step by Step Solution

1. Step 1: Write the proportion equation
   407.50 : 631.31 = 631.31 : x
2. Step 2: Convert to fraction form
   407.50/631.31 = 631.31/x
3. Step 3: Cross multiply
   407.50x = 631.31 × 631.31
4. Step 4: Simplify right side
   407.50x = 398,555.47
5. Step 5: Solve for x
   x = 398,555.47/407.50
6. Step 6: Final answer
   x = 978.05