Finding the Third Proportional to 257,412 and 389,443.50

Step by Step Solution

1. Step 1: Write the proportion equation
   257,412 : 389,443.50 = 389,443.50 : x
2. Step 2: Convert to fraction form
   257,412/389,443.50 = 389,443.50/x
3. Step 3: Cross multiply
   257,412x = 389,443.50 × 389,443.50
4. Step 4: Simplify right side
   257,412x = 151,666,239,692.25
5. Step 5: Solve for x
   x = 151,666,239,692.25/257,412
6. Step 6: Final answer
   x = 589,196.46