Finding the Third Proportional to 257,556 and 393,985.50

Step by Step Solution

1. Step 1: Write the proportion equation
   257,556 : 393,985.50 = 393,985.50 : x
2. Step 2: Convert to fraction form
   257,556/393,985.50 = 393,985.50/x
3. Step 3: Cross multiply
   257,556x = 393,985.50 × 393,985.50
4. Step 4: Simplify right side
   257,556x = 155,224,574,210.25
5. Step 5: Solve for x
   x = 155,224,574,210.25/257,556
6. Step 6: Final answer
   x = 602,682.81