Finding the Third Proportional to 239,483.50 and 399,123

Step by Step Solution

1. Step 1: Write the proportion equation
   239,483.50 : 399,123 = 399,123 : x
2. Step 2: Convert to fraction form
   239,483.50/399,123 = 399,123/x
3. Step 3: Cross multiply
   239,483.50x = 399,123 × 399,123
4. Step 4: Simplify right side
   239,483.50x = 159,299,169,129
5. Step 5: Solve for x
   x = 159,299,169,129/239,483.50
6. Step 6: Final answer
   x = 665,178.06