Finding the Third Proportional to 199.50 and 399.38

Step by Step Solution

1. Step 1: Write the proportion equation
   199.50 : 399.38 = 399.38 : x
2. Step 2: Convert to fraction form
   199.50/399.38 = 399.38/x
3. Step 3: Cross multiply
   199.50x = 399.38 × 399.38
4. Step 4: Simplify right side
   199.50x = 159,500.39
5. Step 5: Solve for x
   x = 159,500.39/199.50
6. Step 6: Final answer
   x = 799.50