Finding the Third Proportional to 257,499 and 393,910.50

Step by Step Solution

1. Step 1: Write the proportion equation
   257,499 : 393,910.50 = 393,910.50 : x
2. Step 2: Convert to fraction form
   257,499/393,910.50 = 393,910.50/x
3. Step 3: Cross multiply
   257,499x = 393,910.50 × 393,910.50
4. Step 4: Simplify right side
   257,499x = 155,165,482,010.25
5. Step 5: Solve for x
   x = 155,165,482,010.25/257,499
6. Step 6: Final answer
   x = 602,586.74