Finding the Third Proportional to 355.50 and 389.25

Step by Step Solution

1. Step 1: Write the proportion equation
   355.50 : 389.25 = 389.25 : x
2. Step 2: Convert to fraction form
   355.50/389.25 = 389.25/x
3. Step 3: Cross multiply
   355.50x = 389.25 × 389.25
4. Step 4: Simplify right side
   355.50x = 151,515.56
5. Step 5: Solve for x
   x = 151,515.56/355.50
6. Step 6: Final answer
   x = 426.20