Finding the Third Proportional to 405.56 and 629.30

Step by Step Solution

1. Step 1: Write the proportion equation
   405.56 : 629.30 = 629.30 : x
2. Step 2: Convert to fraction form
   405.56/629.30 = 629.30/x
3. Step 3: Cross multiply
   405.56x = 629.30 × 629.30
4. Step 4: Simplify right side
   405.56x = 396,014.56
5. Step 5: Solve for x
   x = 396,014.56/405.56
6. Step 6: Final answer
   x = 976.46